4 wt suspension fluid and fork oil from Motorex.  Ideal for all fork and shock appliations requiring a fluid around 16 cSt.  Try Shockcraft's simple fork oil selection charts to find out which oil you need for your brand of fork, terrain, climate and riding.

Fox Racing Shox use Motorex 4wt oil in its MY21 DHX2 and FLOAT X2 shocks.

Viscosity:
16 cSt at 40 degrees Celsius
5 cSt at 100 degrees Celcius
VI  250
Pour Point <-40 degrees Celcius

(source: Motorex TDS).