Fits Type 4 and 12 enclosures which have external screw clamps. Requires only a quarter-turn (90 degrees) to open or close. An internal O-ring and external gasket assure a water-tight and dust-tight seal. Installation requires a hole punched or drilled in the door for each latch. Complete instructions are furnished. A square or triangular key is required for tamper-resistant latches. Latch is die-cast zinc with chrome finish.