Additional Drilling Equipment - This listing is for Mud Pump Piston Half FH 5 1/2 - 14/15 Mission 011103132 National Oilwell Varco Brand New! Outer box has wear and tear and dust from warehouse storage, but the piston is still sealed in original bag inside the box. Free Shipping! Please check our feedback and buy with confidence! Topline433. Location: Grand Prairie, Texas. For complete listing information please select the Click To Bid button to see this item on eBay.