The Model 3900 is designed for use on light-duty commercial standard and high lift (5 ft. high lift max) sectional doors. Maximum recommended duty cycle: 10 cycles per hour.
All LiftMaster Openers and Operators should be purchased through a Dealer and professionally installed.
Main Office: (814) 371-7358
Clearfield Office: (814) 762-8100
Punxsutawney Office: (814) 938-3332