Tamron Adapt-A-Matic 80-250mm F/3.8 Model PZ-20Au: This lens was available in three versions. We are not sure if the PZ-20Au model name applies to all three versions. Initially there was the first model which featured metal knurled focus and zoom rings. Then there was a subsequent model which featured rubber focus and zoom rings yet still did not have slots on the aperture ring for the aperture coupling band included with later versions of some Adapt-A-Matic mounts. The final version of this lens features rubber focus and zoom rings plus the slots for aperture coupling bands.

Lens Specifications:

Lens Model	PZ-20Au
Focal Length	80-250mm
Aperture Range	f/3.8 — 22
Angle of View	30°~10°
Optical Construction (Groups / Elements)	9 / 14
Min. Focus from Film Plane	79" (2.0m)
Macro Mag. Ratio	—
Filter Size	72mm (front)
Diameter	3.0" (76mm)
Length at [w/Nikon mount]	[9.2" (233mm)]
Weight	45.1 oz. (1280g)
Lens Hood	Built-in
Accessory	—