Mounting a basin tap is an instance of the through-hole clamped fixture: the tap body bears on the upper face of the basin while a backing plate and threaded studs draw it downward from below, so the fixture is held by clamping force distributed across a rigid plate rather than by fasteners engaging the basin material itself — a necessity because vitreous china and similar substrates carry compression but fail under point loading. Sealing at the deck is achieved by an elastomeric O-ring or gasket seated in a groove and compressed by that same clamping load, while sealing at each pipe connection is achieved independently by a resilient washer inside a union nut, so that thread torque serves only to develop compression and never to make the seal by interference. The concept belongs to domestic water-supply plumbing within building services, and depends on the flexible braided connector and the isolating service valve as the components that decouple a rigid fixture from rigid pipework and permit maintenance without draining the system.
Mounting a basin tap is an instance of the through-hole clamped fixture: the tap body bears on the upper face of the basin while a backing plate and threaded studs draw it downward from below, so the…