The trunion pins through each lever arm have a round ball bearing assembly at the top and bottom. Additionally, a second flanged ball bearing is used at the bottom of each pin. The 3 ball bearings per lever arm allow the lever arms to turn completely freely, and the lack of spring tensioning means there is no other physical part touching the arms. No physical impediment to lever arm movement means a good adjustment range and a light touch for the operator regardless of where the magnet tensioning is set (a matter of personal preference).
As the dit or dah lever is pushed to send a character, the opposition magnet tensioning pushes the lever back towards the center post on release.
Adjustments: The ZN ULTIMATE uses oppositional magnet tensioning. Each lever arm for the dit and dah sides of the key has a magnet installed, with opposing magnets installed in the tensioning screws that are inserted through each side of the mainframe of the paddle.
There are no adjustments needed for lever arms. 2-56 allen head set screws are inserted into the mainframe at the 4 points where the round ball bearings are installed. These set screws ensure the lever arms and their bearings do not slip when the key is being transported or shipped. The bearings themselves precision fit to a tolerance of +/- .001 inch inside the mainframe and are permanently installed, the set screws are merely extra insurance for rough handling to assure they do not move if the key is hit hard in transport or otherwise maltreated.
The top mainframe is cast zinc, chrome plated as used on other VIBROPLEX products. The base is cold rolled circular steel stock, chrome plated. Tensioning screws, posts, lever arms are made of brass, chrome plated. Finger pieces are blue acrylic stock. All parts with the exception of the connection cable to the radio are MADE IN USA. All physical assembly is done in Knoxville, TN, USA.
Contact points are large relay contacts made of 99.4% coin silver and are for lifetime use.
3 wire cable with 3.5mm plug is standard and attached to the key.