Size 2 - 4. The D1200 Overhead Door Closer from Ryobi has an adjustable strength size from 2 - 4 depending on how it is mounted. With fully adjustable closing, latching speed and backcheck, the D1200 is a versatile choice of overhead door closer. It has been performance tested to 500,000 cycles for reliability and it is easy to install. The D1200 is suitable for both commercial and domestic applications as well as for closing insulated fire doors. Features optional backcheck. Strength size 2 - 4 adjustable via mounting position. Tested to 500,000 cycles. Reversible handing