BD Loops 6' x 14' Preformed 3 16" Saw cut 40 Foot Loop Model:100' Lead in (SC 40 100) Doorking Microphone Board Kit Without and VoIP phones without Doorking Microphone Board Kit Without Harness For 1808 The Manual Release mechanism is a key operated device that disengages (or engages) the gears in the 390 24V Operator The entire loop including the lead in fits within a 3 16” saw cut groove preventing wasted time spent double saw cutting or doubling blades to cut the home run lead in allowing the installer to apply a sealant to a flat surface and resulting in at least a 30% savings in loop sealant to seal the groove vs