Liftmaster 841LM Automatic Garage Door Lock

Features: Automatic operation, performs in tandem with the opener, so it always locks and unlocks. Anywhere assurance, smartphone monitoring with the myq app means homeowners always know that the garage is securesafety and security: Absolute protection, the automatic deadbolt lock makes the garage door virtually impenetrable audible security, the sound of the lock engages providing homeowners with assurance that the door is closed and secure. Compatibility: Works with three new select lift master auto lock capable garage door openers 8550w dc battery backup belt drive wi fi 8587w ¾ hp ac chain drive wi fi 8360w dc battery backup capable chain drive wi fi.

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The 841LM works automatically with your garage door opener so it always locks and unlocks with every operation of the door.
The model 841LM 12V lock is only compatible with the following garage door opener model numbers: 8550WL, 8587WL, 8360WL, 8500W.
It is not interchangeable with the 24V lock used on residential jackshaft garage door opener models 3800, 3900 and 8500.
Add a lock to each side of the door for the best defense against high winds and storms and intruders