Abstract: A releasable anchor connector for a tension leg platform in which a tether with a bore is locked in a template insert at the seabed by means of a series of locking fingers acting through a ring and a resilient connector. The tether is unlocked by locating a ram that disengages the fingers at the end of the bore and applying hydraulic pressure to the ram by means of a hose passed down the bore and a delivery head at the end of the hose. The delivery head comprises a hollow body, a piston slidable in the body and a valve member slidably mounted on the piston. A spring urges the valve member to engage a valve seat and a spring urges the piston forwards. Hydraulic pressure of the fluid in the hose forces the piston back so that a split collet moves back with the piston and expands to hold the delivery head in the position behind a shoulder formed in a bore leading to the ram, after which the piston lifts the valve member off its seat, so transmitting the hydraulic pressure to the ram.