BARNDOORS

A rotatable attachment consisting of two or four metal flaps (hinged) which is fixed to the front of a Fresnel or PC type lantern to cut off the beam in a particular direction(s).

BOWLINE

Most riggers' knot of choice. Secure and easy to undo after heavy loading.

BREAKOUT

A connection at the end of a multicore cable which allows the connection of many items to it. (e.g. there is a breakout box at the end of a sound multicore cable which allows you to plug microphone cables into it).

BUMPER

Heavy duty steel frame used to hang speaker clusters overhead during concerts and other large shows