Jupiter-37A (-37A), black lens for SLR camera
135 mm, f/3.5, M42 mount, s/n 8161738, 
Kazansky Optical Mechanical Plant (KOMZ), Kazan', USSR, 1981

Very good condition. Lens is clear and clean, does not have any fungus. Front glass has tiny, almost invisible cleaning microscratches. Inside there can be microspecks of microdust. Aperture and focus rings rotate properly and fluently. Aperture blades have oil. Body has signs of age and use.

I took a test photo with this lens set on DSLR "Sony A-100" via adapter. Test photo is #3.

Camera "Zenit E" is not included.

"Jupiter-37A" is USSR high-speed fixed manual telelens which was based on German Carl Zeiss Sonnar 3.5/135. Letter "A" means that with adapter this lens can be mounted on camera with mounts: M39*1/45.2, bayonet H (Nikon F), bayonet K (Pentax K-mount) and others. 
It was produced at KOMZ in 1978-2009. This lens has one-layered anti-reflection coating.
Lens has 12 aperture blades which form ideal round hole. Aperture meaning is changed fluently, not discrete.
Body is fully metallic.
Lens has warm colour reproduction. Photo with this lens is extremely sharp and three-dimensional. Background is blurred very nice.
Lens does not like contre-jour and side light, so lens hood is recommended.
It is one of the best USSR portrait lenses. 
Variants:
"MC Jupiter-37A" was produced in 1983-1989, has multilayered anti-reflection coating
"Jupiter-37A MC-H-30" was produced in 1983, has multilayered anti-reflection coating
"Jupiter-37AM" and "MC Jupiter-37AM" - produced in 1990-2002, changed body and lowered weight.
"MC Jupiter-37K" - produced since 1985, Pentax K-mount. 
Price for this lens was rather high and depended greatly on type of anti-reflection coating: 55 Soviet Roubles for usual "Jupiter-37a" and 100 Soviet Roubles for "MC" version. Average salary was 120 Soviet Roubles per month.
Lens offered has "USSR Quality Mark" meaning that this lens has higher quality than ordinary lenses.

Characteristics: 
Lens s/number - 8161738
Number of lenses - 4 in three groups, Sonnar
Angle of view - 18o 
Number of aperture blades - 12
Limit of aperturing - 1:3.5 (max), 1:22 (min)
Resolving power - (centre/edge) 45/30 lines/mm
Minimal distance of focusing - 1.2 m
Type of thread - M42x1/45,5 mount
Type of thread for the nozzles - M52x0.75 mm 
Dimensions (mm): 90*57*57
Focal distance - 135 mm.
Mass - 377 g