Weldable steel tube clamps for 1- 1/2" o.d. tubing Clamp I.D. = 1-7/16" (undersized for great clamping grip.) Clamp o.d. = 2.5" Clamp height = 2.25" Clamp thickness= 1/2" Includes 4 stainless steel allen bolts per clamp Material is 1018 steel. Made In The USA by a US manufacture. Quality you can count on.