Lathem LX100 - Manual (Page 25)

LX100 User’s Guide
Page 25
14. Install 4 new AA (1.5 volt) alkaline batteries (not included)
into battery pack on Interior handle. Make sure they are
installed in the correct direction and are firmly seated in
position. You will hear a buzz, indicating the lock is
energized.
15. Place Interior handle cover over battery pack and secure
with 2 screws on top and bottom. Do not over-tighten the
Interior handle! Doing so may affect the performance of the
lock.