These universal mounts are designed to surround and clamp the projector. The ball & socket design offers complete, integrated security from the projector to the ceiling and multi-directional positioning for proper lens alignment. One security screw adjusts yaw (360?oll( /-15O), & pitch ( /-15O). Complete Armor Lock security at every connection point. Note: For a complete installation one extension column or flush mount tube and one ceiling fixture are required with mount. All units have a maximum load capacity of 50 Lbs.Inside Dimensions: W 7.5" to 11.5" H 2" to 3.75" Weight: 7lbs.