Parker Fly Handbook page 14

Vibrato Bridge
Action is adjusted by turning the two hex-head
screws on the back of the guitar. Using the L-
shaped 5/32 Allen wrench supplied with your guitar,
turn the screws clockwise to lower the bridge, and
counterclockwise to raise it. To make a large adjust-
ment, alternate between the two screws. Do not
turn them more than a turn at a time.
Non-Vibrato Bridge
Action is adjusted by turning the three screws in
the back of the guitar. Using the T-handle
3/32 Allen wrench supplied with your guitar,
turn the screws clockwise to raise the bridge,
and counterclockwise to lower it. To make a
large adjustment, be sure to keep the bridge
level. To do this, alternate between the three
screws, turning them no more than a turn at a
time.