Set of 4 high quality 4 in line bass tuners by Schaller.  Available in Nickle TK791, or Gold TK792

Top mounting holes holes are 13/16th inches.
Bottom holes are 11/16th inches.
Top hole to bottom hole is 1 3/8 inches.
Shaft is 9/16th inches.
Bushings and screws included.

Gold Tuning Machine Set Is $109.99