Lorient LAS8002 si Fire Door Drop SealLorient LAS8002 si Fire Door Automatic Drop Seal is face fixed (or semi mortised) and features a silicone rubber gasket and internal fins. It is used to close the compliant gap under single swing fire doors to maintain their acoustic, smoke, and energy efficiency performance. The drop seal incorporates a high efficiency spring loaded mechanism that extends the seal as the fire door swings shut and automatically retracts it as the fire door is opened