Clamp - video

Clamp. By KEVGEN MASTER. 4:12 video:

https://www.youtube.com/watch?v=9GVyzYWlNoA

Seems like the sliding jaw would damage the threads. Also, not being a flat top thread (like acme) it would be prone to knicks. The jam nut action on the bottom of the movable jaw also seems a source of thread damage...