SMC Pentax-M 135mm f3.5 brand_Soligor It's about the size of

It's about the size of a pack of

but it pays off in storage capacity and light weight

the camera end is a standard F mount but practical compatibility will depend on the shape of your camera (some bulkier AF and digital cameras will require an additional extension tube- not included- to clear the back of the rail)

or you can use it by itself in case you're just curious how far away something is

I'm not sure what a Neewer is

SMC Pentax-M 135mm f3.5 brand_Soligor It's about the size ofThe SMC Pentax M 135mm f3. 5 lens is a compact short telephoto lens for Pentax K mount SLR cameras. In good condition, with some cosmetic paint wear, minor internal dust, good function.