They are key operated from the outside and lever handle operated from the inside. The latch automatically deadlocks on closing the door and the snib function (bolt hold back button) enables the latch to be held back.
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P 77 Traditional Nightlatch. Excellent Yale quality. This lock is designed to fit wooden doors. Rest assured this is a genuine Yale product. The centre of the keyhole must be 60mm from the edge of the door.
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The Yale 82 deadbolt nightlatch is a standard security nightlatch that has a deadbolt and no intermediate latching action. It is ideal for flat and communal entrance doors which allow for key operation from the outside and turn handle from the inside. It is supplied with an anti-bump 1109 rim cylinder and 2 keys. The Yale 82 deadbolt nightlatch comes with a 2 year a guarantee.
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This Yale P1B has a hardened case finished in Brasslux. Locks with a 40mm backset are normally used where there is restricted space, such as on a narrow glass panelled door. Yale's High Security P1 Double Nightlatches are suitable for timber external doors and are ideal for glass panelled doors.
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Large yale high security door lock new 92mm  wide also have the smaller one at 64mm white if needed just let me know which one you want 
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Condition - New, Box shows signs of wear and tear from storage. Photo's are provided for you to inspect the condition of the item.
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The Yale 82 deadbolt nightlatch is a standard security nightlatch that has a deadbolt and no intermediate latching action. It is ideal for flat and communal entrance doors which allow for key operation from the outside and turn handle from the inside. It is supplied with an anti-bump 1109 rim cylinder and 2 keys. The Yale 82 deadbolt nightlatch comes with a 2 year a guarantee.
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