BOSS 12 way adjustable shock absorbers are at the forefront of shock absorber technology.
100% oil filled with a closed cell foam insert ensure continued high performance under harsh conditions.
Why 100% oil filled as opposed to gas/oil? It all comes down to cost.
Gas/oil shocks are cheap to make because the nitrogen. (Which is one of the cheapest gases around) takes the place of where oil should be (oil costs more).
If you pull one of these shocks apart you will notice there is only just enough oil to cover the piston and valve. Once this small amount of oil gets hot it relies on the gas pressure to stop it aerating.
Therefore the higher the gas pressure the more chance the shock will not work at all when it gets hot. As the pressure forces the valves open (even pressure both sides also called cavitation).
BOSS shocks use a 22mm hard chrome shaft, dual seals (wiper and oil) along with 50mm outer body.