The mast clamps are suitable to mount an antenna on a pipe/ pole, or attach one pipe to another pipe to mount an outdoor antenna Using the V jam brackets with U-, the clamp kit can securely hold pipes and antenna tight and in place,will not budge in the wind Dimension: support pipe with diameter raging from 098inch to 21inch/24mm-54mm; Weight:290g Material: quality stainless steel with anti-rust coating finish Colour:As shown Material:Metal Size:14 x 52cm Package Contents: 2 Set x Double Antenna Mast Clamp V Jaw Block with U Bolts Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.