If you ever need to refill or top off the fluid in your Ritchie compass, the manufacturer recommends Isopar L, an odorless, colorless, refined synthetic fluid. Its low viscosity promotes quick swinging. Won’t freeze or boil off at temperatures from -40º to 200º F., and it may be mixed with the mineral oil already in compasses made before 2001.
Price : $19.99
Brand : E.S. RITCHIE & SONS, INC