This a pair of tube clamps with a threaded stud. Primarily used to mount a Hi-Lift jack on one of our Jeep rear tire carriers, but can be used on any 1-1/2" diameter tube.
The clamps are precision machined with two recessed allen head bolts to secure it in place.
They are very heavy duty, but should be used for the mounting trail gear (gas cans, jacks, racks, trail tools, etc.).
Threaded stud size is 3/8-16 x 1" long with wing nuts and washers as pictured.
Sold as a PAIR.

NOTES:
Also offered in a 1-3/4" version (BCL3502).
Please do not use for any application that would risk your personal safety.