The SIMPSON replacement spray gun is for cold water machines & is designed to replace or upgrade your existing spray gun for your pressure washer. This spray gun is equipped with a trigger safety lock-out & can be used with pressure washers with standard threaded high-pressure hose & Wand connections. The gun has an ergonomic design & easy pull trigger helps reduce hand fatigue for all day use. Designed to fit most gas pressure washers & is ratedup to 3400 PSI. Max temperature: 140° Fahrenheit/ cold water hardware/fittings: threaded M22 connection x threaded M22 connection ratedup to 3400 PSI ergonomic design & easy pull trigger for comfort & ease of use equipped with a trigger safety lock-out standard threaded fittings hose & Wand connections cold water pro-style replacement gun designed to fit most gas pressure washers.