What is 3M's Dual Loc system?

3M's Dual Lock backing is a system of mushroom shaped plastic pegs aligned onto the backing material and on the mandrel. The diamond disks "snap" onto the mandrel and are held in place until you pull them free. They have a tremendous amount of shear strength that keep the diamond disks applied to the mandrel even if they are placed off center. 

The Dual Loc system is a great alternative for customers who have problems with the Velcro backed disks holding onto their mandrels as they work. The diamond disks are not as flexible as the velcro backed diamond disk, but not as rigid as the Roloc diamond disks.