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A W Faber 309, 51/91/309
(25cm Scale, Enhanced Mannheim, School use)
Examples: 1934, 1938
Version Comparison
Two examples of the model, one from the early numbering system and one from the interim numbering system, fully detailed below, differences summarised as follows:
Click on a column heading to jump down to version images and detailed description.
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1934 |
1938 |
Front Scale Labels:
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-
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A, B, C, D
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Slide Rear Scale Labels:
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S, L, T
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sin, lg, tg
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Decimals:
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Units
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Tenths
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Cursor Runners:
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Machined block
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Folded strip
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Origin Labelling:
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Printed
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Stamped
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Click on the images for enlargements.
A W Faber 309 (1934) |
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Summary
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System:
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Enhanced Mannheim
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Specialization:
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School use
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Type:
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Closed frame
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Material:
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Pearwood
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Facings:
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Celluliod
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Scale Length:
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25cm
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No of Scales:
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7
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Front Length:
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300mm
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Front Width:
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30mm
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Language:
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English
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Origin:
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Bavaria
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Date:
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1934, December
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Features/Notes:
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-
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Scales (colours as shown)
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Front:
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A [ B, C ] D
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Back:
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[ S, L, T ]
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Labels Left:
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-
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Labels Left:
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All, as scales
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Labels Right:
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-
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Labels Right:
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All, as scales
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Style:
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Normal
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Typeface:
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Sans-serif
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Extensions:
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-
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Decimals:
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As units between 1 & 2 on C & D
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Gauge Marks:
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p (3.14) on A, B, C & D
M (1/p=0.318) on A & B
C (1.13) on C
C1 (3.57) on C
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Rulers:
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cm on back, upper edge
inch on back, lower edge
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Features/Notes:
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-
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Construction
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Stock:
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2 part split stock joined with steel springs (DRGM 522689, 1912; DRGM 452965, 1911).
Braced with longitudinal metal strips (DRP 206428, 1908).
Left and right viewing cutouts with index marks, in back for reverse of slide.
Square top and bottom edges.
Double cursor grooves enabling cursor to be turned around and used on the back.
Flat back.
Front, back and well celluloid faced.
Length x Width x Height (mm) - 300 x 30 x 9
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Slide:
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Double sided
Braced with longitudinal metal strips (DRP 206428, 1908)
Celluliod faced on both sides
Front face width (mm) - 13.5
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Cursor:
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Freeview (DRP 465658, 1927), glass pane.
Top and bottom aluminium runners machined from block.
Left end riveted steel spring on top runner.
Single central full length hairline.
Width x Height (mm) - 29 x 36
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Printing (colours as shown)
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Stock:
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"309" + scales logo + "A.W. FABER" in centre of well above split, sans-serif.
"D.R.G.M." in the centre of the well below the split, sans-serif.
"MADE IN BAVARIA" in the well, above the split towards the right end , sans-serif.
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Slide:
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-
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Cursor:
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"MADE IN BAVARIA" and "1" stamped on the edge of the top runner, sans-serif.
"A.W. FABER." and "D.R.P" stamped on the edge of the bottom runner, sans-serif.
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Labels:
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None
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Instructions
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None
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Box (colours as shown)
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Style:
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Square
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L x W x D mm:
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305 x 45 x 18
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Material:
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Cardboard
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Colour:
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Black
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Construction:
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2 part, internal sleeve join.
Faced.
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Printing:
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scales logo + "A.W. FABER'S" and underneath "Calculating Rule for School use" on the front.
Round indentations on the front either side of the opening.
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Labels:
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"309" and underneath in smaller type "MADE IN BAVARIA" on black, on both ends.
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Detail Images
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Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
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Click on the images for enlargements.
A W Faber 51/91/309 (1938) |
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|
Summary
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System:
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Enhanced Mannheim
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Specialization:
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School use
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Type:
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Closed frame
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Material:
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Pearwood
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Facings:
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Celluliod
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Scale Length:
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25cm
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No of Scales:
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7
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Front Length:
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300mm
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Front Width:
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30mm
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Language:
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English
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Origin:
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Bavaria
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Date:
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1938, July
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Features/Notes:
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Transitional model numbering system, model continuation from '309'.
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Scales (colours as shown)
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Front:
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A [ B, C ] D
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Back:
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[ S, L, T ]
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Labels Left:
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All, as scales
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Labels Left:
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[ sin, lg, tg ]
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Labels Right:
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All, as scales
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Labels Right:
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[ cos, lg, tg ]
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Style:
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Normal
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Typeface:
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Sans-serif
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Extensions:
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-
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Decimals:
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Tenths between 1 & 2 on C & D
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Gauge Marks:
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p (3.14) on A, B, C & D
M (1/p=0.318) on A & B
C (1.13) on C
C1 (3.57) on C
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Rulers:
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cm on back, upper edge
inch on back, lower edge
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Features/Notes:
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-
|
Construction
|
Stock:
|
2 part split stock joined with steel springs (DRGM 522689, 1912; DRGM 452965, 1911).
Braced with longitudinal metal strips (DRP 206428, 1908).
Left and right viewing cutouts with index marks, in back for reverse of slide.
Square top and bottom edges.
Double cursor grooves enabling cursor to be turned around and used on the back.
Flat back.
Front, back and well celluloid faced.
Length x Width x Height (mm) - 300 x 30 x 9
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Slide:
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Double sided
Braced with longitudinal metal strips (DRP 206428, 1908)
Celluliod faced on both sides
Front face width (mm) - 13.5
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Cursor:
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Freeview (DRP 465658, 1927), glass pane.
Top and bottom aluminium runners fromed from folded strip.
Left end riveted steel spring on top runner.
Single central full length hairline.
Width x Height (mm) - 30 x 37
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Printing (colours as shown)
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Stock:
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"51/91/309" + scales logo + "A.W. FABER" in centre of well above split, sans-serif.
"D.R.G.M." in the centre of the well below the split, sans-serif.
"MADE IN BAVARIA" stamped in the well, above the split towards the right end , sans-serif.
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Slide:
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-
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Cursor:
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"MADE IN BAVARIA" stamped on the back of the top runner, sans-serif.
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Labels:
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None
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Instructions
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None
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Box (colours as shown)
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Style:
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Square
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L x W x D mm:
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308 x 45 x 17
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Material:
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Cardboard
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Colour:
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Black
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Construction:
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2 part, internal sleeve join.
Faced.
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Printing:
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scales logo + "A.W. FABER'S" and underneath "Calculating Rule for School use" on the front.
Round indentations on the front either side of the opening.
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Labels:
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"51/91" and underneath in smaller type "MADE IN BAVARIA" on black, on both ends.
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Detail Images
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Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
Click on the images for enlargements.
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