The Lincoln Electric Magnum Pro Gun Tube Insulator (KP2773-2) is a replacement insulating component used on Magnum Pro 250A and 350A MIG guns. It helps maintain proper electrical isolation at the gun tube interface and supports consistent current transfer and torch reliability during daily welding. Use this part when the original insulator is cracked, heat-damaged, carbon-tracked, or loose, or anytime you’re rebuilding the front end to correct intermittent output, arcing where it shouldn’t be, or poor consumable life. Includes: 1x gun tube insulator (Qty 1). Fitment note: Confirm your gun model and parts breakdown before ordering—Magnum Pro front-end parts vary by gun series and generation.