Newport kinematic mirror and lens mount Similar to KM100 Description: nice lens kinematic mount removed from High School laser lab. Measures: 2x2" (51x51mm). The lens holder is a bit smaller, around 51x49mm. It holds 25,7mm and smaller lenses (down to aprox. 22mm with actual "8-32" locking screw). If you want to hold lenses 22mm you need a larger "8-32" imperial type screw, (for example: https://www.newport.com/p/DE-8-0.63). Lenses seat in a couple of plastic little bases that protrude a little bit and they are held in place through an allen screw ended in plastic tip (which avoids scratching or damaging expensive optics). The big hole is Ø 31,70mm (1,25"). It has 8-32 thread mount to mount in breadboard or other components (remember "8-32" is similar to M4 but with bigger thread pitch). Screws are metal 100 TPI. High quality. Condition: normal usage marks. Nice working condition. Note: these items have been de-greased, cleaned, re-greased (with special oil, better than original grease) and checked for missing or damaged parts. Then tested and verified ok. Good functioning is garanteed. Issues: some marks of normal usage here and there.