Systems, devices and methods for pipe connectors and associated components are disclosed. Features for no hub clamps, for locking mechanisms on no hub clamps, for tools for no hub clamps, and for gaskets are described. The gaskets may be hourglass-shaped or otherwise taper outward near the ends to facilitate assembly onto pipe ends and that compress inward when a clamp is secured over the gasket. The gaskets may reduce in circumference at the gasket ends upon contraction of the gasket by a clamp onto two pipe ends. The gaskets may include collapsible sections that collapse upon contraction of the gasket by a clamp onto two pipe ends.