This kit is used to provide a guiding path for optical fibre cords, whilst maintaining the MBR at 30mm. It can be used in two ways. Firstly across the top of adjacent 600mm x 300mm racks; and secondly across the top of 2 x 600mm x 300mm back to back Equipment Racks. Included is a prepared straight length of 50mm duct to which can be fitted 2 x down elbows; or 2 x horizontal elbows each connecting to a short straight length of 50mm duct, which in turn are fitted to the 2 x down elbows. The first description describes a 50mm duct top feed between adjacent racks. The latter description describes a 50mm duct feed across the top of back to back equipment racks. Mounting brackets are provided for the 50mm duct, which in turn connect to 4 x 15mm high extension mounting brackets that fasten the duct system to the rack top. Supplied are 4 x mounting crews and nuts. The fibre cord radius is maintained at both entry and exit, where curved entry guides are fitted. The duct kit is made from 50mm x 50mm standard duct items. For assembly at site, for both cord entry/exit points: first fit, duct mounting brackets to each side, with the extension bracket facing outwards. Next, fit the 2 x 50mm duct joiners [supplied loose], followed by the 50mm outlet, 90 degree, down elbows.