See: HUDY

HUDY have introduced a new 80mm to 140mm adjustable droop gauge for 1/8th Buggies and E-buggies as well as 1/10th Buggies, Short Course trucks. The professional fully-adjustable droop gauge is CNC-machined from premium-quality aluminum and comes black coated and laser engraved with a precision scale. Designed to check the droop of the suspension downtravel in range 80mm to 140mm, the tool is ideal for quick and instant droop check directly on ready-to-race car with no other set-up equipment needed. 

The gauge is inserted on the nut that holds the shock on the shock tower and using the ruler on the gauge measure the distance to the center of the screw that mounts the shock absorber to the suspension arm. The adjustable slider allows to set the measured length on one side of the car and exactly duplicate it on the other side. To adjust the droop adjust the downstop screws as needed or adjust the length of the shock absorbers.