The Hi-Mound HK-706, HK-707, and HK-708 are identical straight keys using either a clear cover (HK-706), black cover (HK-707) or no cover installed (HK-808). The clear or black covers are removable to adjust contact spacing and spring tension. Instead of rubber feet, these keys utilize a clever rubber stripping around the bottom circumference of the key to keep them from moving on the table. Push it with your finger - it won't move. Screw hole near the front to allows the key to be permanently affixed to a table if desired.
HK-707 with black cover economy priced at $99.95.