Quantity   Component name
1 × 100 W white LED $5-7
1 × LED reflector & collimator $4
1 × CPU heat sink with fan and mounting bracket $3-10
1 × DC-DC buck-boost converter with fan $7
1 × rechargable batteries $10-20 ????
1 × voltage gauge with led display $2
1 × power switch, potentiometer, etc salvaged parts
1 × steel, aluminum, wood, plastic, nuts and bolts, etc for the frame found/salvaged parts