Specifications: 

Focal Length 50mm
Lens Mount ARRI PL
Format Full Frame
Image Circle 46.5 mm
Maximum T-Stop T2.1
Minimum T-Stop T22
Minimum Focus Distance From Image Plane: 1.21' / 0.37 m
Iris Blades 16
Gear MOD & Pitch Focus: 0.8 MOD / 32 Pitch
Iris: 0.8 MOD / 32 Pitch
Front Diameter 80 mm
Filter Thread 77 mm
Focus Scales Imperial
Focus Rotation 270°
Iris Rotation 58°
Electronic Communication No
Length 3.4" / 87 mm
Weight 25.8 oz / 732 g