This fitting straps around a 110mm Soil Pipe to enable a waste pipe to be introduced. A 54mm hole should be cut into the pipe, allowing the lug of the strap boss to fit snugly inside the pipe.Use in conjunction with our SP10, SP11 and SP12 Boss rubber adaptors to introduce waste pipes into the soil stack. The rubbers are a push fit connection into the preformed opening of the strap boss. For more information on connecting waste pipes into soil pipes, visit our step-by-step instruction page. You can also watch our short instructional video detailing how to use the various boss fittings that are available.