The plunger rod is made of high-quality Metal for durability; has a sturdy structure, impact , not easily deformed, has resistance, and is not easy to rust. Ready to build pressure after the pump is connected on sprayers, ensuring that the sprayer can large and stable paint. 246428 246-428 airless pump, applicable to the Aftermarket of airless pump of for / Ultra / Max II 390 395 490 495 595 LineLazer 3400 sprayers. Please shake the pump several times before installing the pump to prevent the internal steel ball from sticking with the alloy plate, which may cause the product to fail to work normally. Do Not Fit For Max 390/395/490/495/595;Do Not Fit For PC Por 390/395/490/495/595;Do Not Fit For Nano (Updated Version). This product is a standard screw pump,not a snap pump,not a PC pump., Weight: 3.33118477882 pounds, Manufacturer: Jaywool