Keys Fitness STRENGTH TRAINER ST-45 Owner's Manual page 7

Assembly
NOTE: Hand tighten bolts and nylon nuts until machine is fully assembled.
STEP 4
Screw Pop Pin (6) into Main Upright (3).
Slide Telescoping Pad Support (4) into Main Upright (3). Pull Pop Pin
(6) in order to choose different settings in Telescoping Pad Support
(4).
Once setting is selected, secure with Knob Bolt (5).
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