This short boss pipe is use in conjunction either with our SP10, SP11 and SP12 rubber boss adaptors or our SP20, SP21 andamp; SP22 solvent weld boss adaptors to introduce waste pipes into the soil stack. One of the openings on the boss pipe is already open, the others are blanked off and can be drilled out as required using a 54mm hole saw. Both ends of the short boss pipe are female sockets which accept plain ended or cut lengths of 110mm soil pipe. These are solvent weld joints. You can also watch our short video detailing how to use the various boss fittings that are available.