AQP Fitting Perm SAE 37

Dura-Kote plating is applied to this fitting specifically to hold up against corrosion. It's a step above standard zinc plating and tends to last considerably longer in outdoor or wet conditions where bare carbon steel fittings would start breaking down. If rust has been shortening your assembly life, this is one of the better options in this size range for that reason alone.

Carbon steel is generally compatible with hydraulic oil, especially with the Dura-Kote plating providing extra corrosion resistance. However, if you're dealing with a particularly corrosive environment or specific fluid requirements, you might want to double-check compatibility charts or consult with a fluid specialist.