[D82F500 multilayer]

Astronomical Telescope d = 82mm f = 500mm Single Film Purpose Lens
Diameter: D 3.2 inches (82 mm).
Focal length F 500mm
Single layer coating film
Combined image quality 1/2-1/4
Diameter Resistant + 0 / -0.12 mm
Center thickness tolerance ±0.2mm
Focal length tolerance ±0.1%
Exit 60/40
eccentric1
Two double adhesive lens groups
Used for astronomical telescope purposes, finders and collimation purposes.