This clamp is a means of attaching either a 220 or 100mm duct system to (up to) 30mm (1”) diameter tube or 25mm (1”) square tubes in an under floor system. It consists of a slotted bracket and U bolt which fit the standard round or square vertical used in most sub floor systems. It is attached to the tube by the bracket and U-bolt, which clamp the tube between the bracket and U-bolt. Two 8mm dia oversize washers are included to aid clamping to square vertical RHS tube, as well as round tube. A single long slot provides a range of horizontal adjustment. The duct-mounting bracket, (220mm duct, Part No: TC1279-13; 100mm duct, Part No: TC1279-14) is mounted at the slot to hold the duct in place. These brackets are available separately.