The McAlpine Black Plastic Captive Plug BP1-Cap is a plumbing component used to cap off a 1 1/2" diameter pipe. It is made of black plastic and is designed to be easily installed and removed, making it a convenient solution for plumbing maintenance and repair. The term "captive plug" refers to the fact that the plug is designed to remain attached to the pipe even when it is removed. This helps prevent the plug from getting lost or misplaced, and makes it easier to reinsert the plug when needed. Overall, the McAlpine Black Plastic Captive Plug BP1-Cap is a simple yet effective plumbing component that is commonly used in residential and commercial plumbing systems. ・ Available in 1½"and 1¾" ・ Only for use with McAlpine wastes which have a centre pin fixing ・ Manufactured in black polypropylene