The ZN-9+ (ZN-9 plus) with 5/16" OTO is built on a 3 1/2" x 3" x 1" steel base and weighs 3.25 pounds. It features 3 ball bearing per lever arm, magnetic return, solid silver contact points and very fine threaded magnet and contact screws (56 TPI). All screws are stainless steel and fingerpieces are black Lexan. The OTO ( outside to outside dimension of the fingerpieces) is 5/16". The lever arms have a parallel arrangement and the OTO cannot be changed.
The ZN-9+ come is Black finish only.