#08 Freeze Plug 1 1/2″ Pipe Use these FREEZE PLUGS to plug the pool pipes after draining or blowing them out. American made, stainless steel bolts and washers with Delrin wing-nuts. Premium pool plugs.Extended winterizing plugs have extra long bolts for plugging deep into a pipe. Use to plug a drain tied into a skimmer (i.e. Anthony Pools), or to plug a wall return pipe cut at an angle.