a Holds objects 1" to 2.25" (25 to 57mm) in diameter. a Each clamp supports a safe working load of 25lbs (11 kilos). a 2 clamps support 50lbs (23 kilos). a Mounts easily with one #10 bolt or screw. a Mounting area: 2 1/2" x 3/4" (64x19mm).