Tuned Drums have many options:

use a rubber mallet to help fit it in

brackets and mounting hardware included

For use with various LiftMaster® Residential and Commercial Gate Operators with Solar Applications

Manufactured to meet or exceed UL325 requirements

LiftMaster Std. Duty Roller Cage Bearing Hinge - Bolt to Gate, Bolt to Post (Black Powder Coat) Sold in pairs. Rollers Tuned Drums have many options:LiftMaster Std. Duty Roller Cage Bearing Hinge Bolt to Gate, Bolt to Post (Black Powder Coat) Heavy Duty Construction for Maximum Durability Dependable Roller Cage Bearing Design Even Weight Distribution Five Times The Weight Bearing Surface of the Nearest Large Hinge Convenient Bolt On Model Easy to Fully Lubricate Specifications: Maximum Gate Weight: Up to 1,000 lbs. per pair. Sold in pairs. Pair (2 per Box) 7. 2 lbs. 3. 2 kgs.