Improvements in and relating to pipe coupling

Disclosed is a pipe coupling for connecting the ends of two tubular conduits, comprising: a pair of casing elements 200, each comprising an outer part 210 and a pair of inner parts 220, the inner and outer parts being rotatable relative to each other, wherein in a first configuration, the pair of casing elements are separate and positionable to surround the ends of the tubular conduits and, in a second configuration, they are locked together, wherein the locking together is achieved by relative rotation of the respective inner and outer parts such that the inner parts of one casing element at least partially engage with the outer part of the other casing element. Further comprising a annular gasket 151, and the inner part 222 having radially inwardly facing projections to engage with a grove in the pipe, as well as pips or teeth to contact or penetrate the surface of the pipe.