All metal head assembly with a knurled metal friction lock and black throttle-type nylon knob. 10-32 UNF-2A threaded output with a 16 degree conical swivel angle mounts using a 1/4″ groove cap. Operating temp: -65 degrees to +230 degrees F. Normal load: 120 lbs tension; 25 lbs compression. Requires a 3/4″ mount hole.