The FXC Dereefer, model DM-500, Part No. 811-00289 is a 100% mechanical mechanism, designed to accommodate a wide range of cargo parachute types and sizes. It is specially designed to be a “re-usable” substitute for the “use-once-and-throw-away” M-21 pyrotechnic cutter. The DM-500 has been designed to fit perfectly into the existing M-21 mounting bracket, no modification required. The timer offers a choice of preset delays of 2 and 4 seconds. Access to the timer external setting screw is quick and easy. The timer mechanism is sealed against all outside elements. The internal subcomponents require no maintenance and are corrosion resistant throughout.