The ZN-SL single lever paddle is built on a 3 1/2" W x 3" D x 1" thick steel base and weighs 3.25 pounds. It features 3 ball bearing per lever arm (total of 9 ball bearings) , magnetic return, solid silver contact points and very fine threaded magnet and contact screws (56 TPI). It has 4 non-skid feet. All screws are stainless steel. The OTO is 3/8" (no other options).