10-inch "Power Trig" Duplex Slide Rule
Frederick Post model 1462 [1945]
Roos model unknown.  (Not SR-113.  SR-113 has scales L, LL, DF [CF, CIF, CI, C]  D, LL3, LL2 and LL0, LL00, A [B, K, CI, C] D, S, ST, T)

Some specimens are marked "No 1462 Power Trig" but most are marked, like this specimen, just "No 1462."
Also made with black end brackets and metal end brackets. 
On Roos-made rules the red ink fades easily and the celluloid facing turns very yellow. 

 

Excerpt from 1945(?) Price List 
Second price is per dozen

Post seems undecided about the name of this slide rule.  The price list above calls it "Power Trig."  I have an advertising brochure for this slide rule which refers to it as "Power Trig" in five different places but the word "Power" has been overprinted with black every time it occurs leaving only "_-Trig".  ("Power" is nevertheless readable under the blackout.) 

I have specimens of this rule with white plastic, black plastic, and metal end brackets.  All are marked "NO. 1462" but only the rule with black plastic end brackets carries the name "Power Trig."  The other two rules carry no model name.
 

 
This scale set  T, DF [CF, CIF,  CI, C] D, S, ST and LL0, LL00, A [B, K, L, C] LL3, LL2, LL1 was new to Post with this slide rule.   It seems to have been so popular that when Post returned to Hemmi they special-ordered the same scale set on new model 1462H.  That rule proved very popular and led, in about 1950, to the Post "Versalog" with the expanded scale set LL0, LL/0, K, DF [CF, CIF, CI, C] D, R1, R2, L and LL/1, LL/2, LL/3 [T, ST, S, C] D, LL3, LL2, LL1 .