Bernard Style 4335 Head Assembly for 300A MIG Guns

Reliable Replacement for Your Bernard MIG Gun

Every welder knows that a smooth arc starts with a healthy front end. If your MIG gun is sputtering, overheating, or giving you inconsistent gas coverage, it might be time to check your diffuser. The P4335 Bernard Style Diffuser Head is a robust, 300-amp replacement part designed to get your torch back in top fighting shape. Built to fit the classic Bernard guns you see in shops everywhere, this head assembly is the workhorse that holds your contact tip and directs your shielding gas exactly where it needs to go.

Why pay more for the brand name when you can get the same performance for less? This diffuser is machined from solid brass, just like the original, giving you the durability you need to withstand the heat of long welds. It accepts the standard elliptical contact tips (the ones you twist 90 degrees to lock in), making tip changes fast and easy—even when you're wearing gloves. The threads are cut clean and deep, so it screws onto your gooseneck securely without wobbling or stripping, ensuring you get full power transfer to your wire.

Gas coverage is key to a clean weld, and a clogged or damaged diffuser is a one-way ticket to porosity city. The P4335 features properly sized gas ports that ensure a smooth, even blanket of shielding gas over your puddle. Whether you are running straight CO2 or a 75/25 mix, this head helps keep the air out and the weld sound. It fits perfectly inside standard slip-on nozzles, so you don't have to worry about alignment issues causing uneven burn-off.

Don't let a ten-dollar part ruin a thousand-dollar job. Keep a few P4335 diffusers in your toolbox. They are compatible with the 200, 300, and 400 amp guns found in heavy fabrication shops, farm repair, and manufacturing lines. Swap out your old, spatter-crusted head for a fresh P4335 and notice the difference in your arc stability immediately.