Purchase method 

1, electric shutter door support manual function, manual easy and fast. Power failure reverse 90 degree clutch, push run. 

2, electric shutter door conventionalpropeller phenomenon cannot exist, we should have a double-sided automatic locking function. 

3, in order to improve the degree of electric rolling door run smoothly, in order to enhance pull, so the plant is driven before and after 8 rounds, even arrange installation technology for gear production. 

4, observe whether the electric roller shutter doors structure precision, lubrication level is good or bad, good electric rolling door cooling comparison, uses the entire gears, no chain, no belt, and enhance the overall life of the shutter movement.