Instructions:
(a) Remove one factory knob from either side of unit.
(b) Turn key clockwise and remove from lock.
(c) Screw GPS/Sounder lock into female thread until tight.
(d) Insert key and turn counter clockwise.
(e) Knob will spin freely when locked correctly making it impossible to remove..
Note: Lubricate often and record key number for replacement keys when lost.

Navman
GD007 (M6 x 1.00 Male Thread)	F4100  |  F4100SX  |  F4150  |  F4150SX  |  F4200  |  F4200SX  |  F4350  |  F4380  |  F4430  |  F4431  |  F4432  |  F4433 | T5430 | T5430(i) |T5380 | T5380(i)
GD008 (M6 x 1.00 Male Thread)	T5100  |  T5100(i)  |  T5110  |  T5110(i)  |  T5380(i)  |  T5340(i)  |  T5500  |  T5500(i)  |  T5505(i)  |  T5600  |  T5605  |  T5605  |  F4500  |  F4600 | F4507 | T5507 | TF6507 | TF6500
GD011 (M6 x 1.00 Male Thread)	TrackFish 6600