Abstract: A trap for crustaceans and fish comprising a plastic mesh forming walls in the shape of a hollow hexagonal prism, made up of two trough shaped parts and end walls. End walls contain frusto conical inlets and interchangeable end walls are closed. Ballast in the shape of elongate extruded hollow square section plastic tubes filled with concrete is fixed to one trough shaped part, an opening in the other trough shaped part can have a frusto conical pipe extending into the trap or a lid, for removing the catch. Tongue and socket connectors for the trough shaped parts have a cross sectional shape for the tongue like a capital letter E with the middle web longer than the outer webs. A bait basket is in two halves which are threaded onto a pin which has a handle at one end and a detent at the other end to clip into a socket in the inner surface of the trough shaped part which carries the ballast.