U-Stop 4" bushing is ideal for penitration points in the slab when using a core bit and can also be used in sump lids. The inside of this bushing has a lip to prevent the PVC pipe from slipping down into the pit. Bushing fits 4" schedule 40 PVC or flared side of schedule 20 PVC. Requires 5" hole in slab.
Radon Professionals
