OEM Microscope Objective - Achromat 40x0.65, Spring

Though no name of the manufacturer is specified, I'm pretty sure that it is LOMO objective. Information below is given in assumption that it is LOMO.

Magnification: 40x
Numeric aperture: 0.65
Iris diaphragm: No
Immersion: None
Tube: 160mm
Cover glass: 0.17mm
Focal length: 4.35mm
Working distance: 0.55mm
Parfocal height: 33mm (RMS)
Correction : Achromat
Spectrum range: 400-700nm
Research method: Darkfield
Contrast method: none