OPW 7HB High Flow Pre-Pay 1" Yellow Leaded Nozzle w/ Anchor Ring For Heavy-Duty, High-Flow Truck, Bus and Fleet Service If you operate a full-service truck stop, refuel your own fleet or manage a card-lock refueling location, the low-cost, long-life and durability of the OPW 7H® high-flow nozzle can help increase your productivity, sales and profits.