USD $275
K+E’s famous Deci-Lon duplex rule, in very good condition. These cases are slightly different, being stitched/formed leather, as opposed to a folded/stitched leather case. Does not include any supplementary sheets or documents. This is K+E’s late production flagship rule, with unbreakable cursor, Ivorite body and adjustable frame, all free of marks, names or initials. Has 8 log log scales, a split square root scale, DI and folded scales. An outstanding and powerful rule, cleverly designed.
Scales include:
Front – Ln-3, Ln-2, Ln-1, Ln-0, A, [ B, T, SRT, S, C, ] D, DI, K
Back – Sq1, Sq2, DF, [ CF, CIF, L, CI, C, ] D, Ln0, Ln1, Ln2, Ln3
Stock: 3
USD $275
K+E’s famous Deci-Lon duplex rule, in very good condition, with very good orange sewn leather case, and supplementary instruction/formula sheets. This is K+E’s late production flagship rule, with unbreakable cursor, Ivorite body and adjustable frame, all free of marks, names or initials. Has 8 log log scales, a split square root scale, DI and folded scales. An outstanding and powerful rule, cleverly designed.
Scales include:
Front – Ln-3, Ln-2, Ln-1, Ln-0, A, [ B, T, SRT, S, C, ] D, DI, K
Back – Sq1, Sq2, DF, [ CF, CIF, L, CI, C, ] D, Ln0, Ln1, Ln2, Ln3
Stock: 1
USD $25
This combination slide rule/ruler comes with the original box and case. The box and case are not in great condition, but the rule has held up well.
Scales are as follows:
Front – A, C, D, K, CF, DF, CI, S, B, L, T
Back – 6″ / 13cm ruler
Stock: 1
USD $49
A single-sided rule for the beginner pocket rule user.
Scales are as follows:
Front – C, D, L, CF, DF, CI
Back – Blank
Stock: 1
USD $45
This 6″ K&E simplex rule features 9 scales, and both imperial and metric rulers on the reverse side.
Scales are as follows:
Front – A, B, C, D, K, CI, S, L, T
Back – Imperial/metric rulers
Stock: 1
Sphere Research Corporation 
