Pyle Mobile Video System PLD58MUT Owner's Manual page 6

INSTALLATION
SPRING WASHER
PLAIN WASHER
TAPPING SCREW
If you want to take CHASSIS out of the SLIDE BRACKET HOUSING,
first remove the PLASTIC COVER of the both sides away, then insert
the two KEY PLATE into left and right side of chassis as above illustration.
HEX NUT
KEY PLATE
DASH BOARD
METAL MOUNTING
STRAP
CONSOLE
SLIDE BRACKET
HOUSING
KEY PLATE
5
HEX BOLT
PLASTIC COVER