Airshok
The AIRSHOK™ is a conventional shock absorber that uses the internal air (gas) pressure to achieve an infinitely adjustable spring rate capability.
All gas pressurized shock absorbers have a spring rate that is determined by the amount of gas pressure in the shock, and the cross sectional area of the shaft. Since typical shock absorbers have shafts that are 1/2” to 5/8” diameter, the cross sectional area is very small,and thus the spring rate is very light.
The AIRSHOK™ has a 1.75” diameter shaft that gives a cross sectional area of 2.4 square inches. The 2.4 square inch area times gas pressure Per Square Inch (PSI) gives the AIRSHOK™ a spring rate that can be used to replace the coil spring.