1, Roll up door openers 2, 24V DC motor drive unit 3, Rolling code technology 4, Safety auto-Reverse 5, ... and reliability, Drive unit housed within the roll ,hardwearing #66 nylon gear mechanism no lubrication required3, Power : 120W( 240W if use use dual motors ... . Push button on control box12, Safety : Safety Reversing The drive unit automatically,reverses should the downward movement of the door be ...