13-Scale All-Plastic Beginner's Slide Rule
Teledyne-Post model 1414 [1972]
Teledyne-Post model 44BB-140 [1972+]  (Some [1972] marked model "1414")

Hemmi model P280

This appears to be another example of changing the model number after the slide rule had been manufactured.  Specimens with both model numbers exist but I'm sure Teledyne-Post never sold this rule under any model number other than 44BB-140.
1972 Teledyne-Post Slide Rule Catalog 

Top:  Teledyne-Post 1414.   Date code "^VD" (April 1971)
Bottom: Teledyne-Post 44BB-140.   Date code "^XF"  (June 1973)