Lens Data:

Years of manufacture: 1963 – 1967
Elements/groups: 4 / 4
Diaphragm type: Pre-set
Angle of view: 28°
Max./Min aperture: 3.5/22
Minimum focus: N/A – Focusing is done with a special designed bellows
Filter size: 49mm
Length: ca. 60mm
Largest diameter: ca. 60mm
Weight: 126 g
Product number: 361; from oct. 66 on 43610, may be seen on underside of auto/man lever

Accessories:

Focusing attachment lens for 253.7 nm (green marked)
Focusing attachment lens for 365 nm (red marked)

Filter for 253.7 nm (IF) (green marked)
Filter for 365 nm (IF) (red marked)
(IF: Narrowband Interference Filter)
Bellows attachment w. special focusing adjustment markings

(data courtesy Asahi Pentax, U.Widén)