Castrol Classic ST90 is a non-EP gear oil with SAE90 viscosity. It is suitable for most types of gears, including helical, spur, bevel, and worm gears, but should not be used in Hypoid gears. The oil offers good anti-oxidant properties and excellent anti-wear protection. Its dimensions are 6.00cm x 11.50cm x 18.50cm and it weighs 1.02kg. It meets API GL3 standards.