281 PRI®/CHEK® VALVE The Lee Company’s new 281 PRI/Chek Valve combines the function of a pressure relief valve in parallel with a check valve into one easy to install insert. The relief valve function features a rugged Tungsten Carbide ball and a 440C seat for durability and long life. The remaining components are constructed entirely of stainless steel. Offered with or without integral safety screens, the 281 PRI/Chek Valve is available in a range of relief flow cracking pressures for system pressures up to 5000 psi. Maximum restriction in the Free Flow Direction is only 300 Lohms* (550 Lohms for screened version). Each Lee PRI/Chek Valve is 100% tested and inspected in both flow directions to ensure reliable, consistent performance. pressure relief valve in parallel with a check valve ■ Durable tungsten carbide ball and a 440C seat ■ Screened version available ■ Designed for system ■ Weighs only 8 grams (9 grams for screened version) ■ Endurance tested to 100,000 relief flow and 500,000 free flow cycles INSTALLATION HOLE Relief Flow Direction Free Flow Direction Screened .281 PRI /Chek Valve PIN INSTALLATION HOLE Relief Flow Direction Free Flow Direction MATERIALS PART Spring Seat Shuttle Plate * The Lohm is a measure of flow resistance. Additional information can be found at www.TheLeeCo.com. Tool Set Part No.: CUTA2810114C Replacement Pin Part No.: SHBA2810003A Body Ball Follower Tungsten Carbide The Lee Company, 2 Pettipaug Rd., P.O. Box 424, Westbrook, CT 06498-0424 PDS 118 1/13 Tel: 860-399-6281 Fax, Order Entry: 860-399-7058 Fax, Technical Information: 860-399-7037 Web: www.TheLeeCo.com

Relief Flow Direction FLOW POINT .281 PRI® / CHEK® VALVE FREE Flow Direction MINIMUM CRACKING PRESSURE (psid) MINIMUM SHUTOFF PRESSURE (psid) CRACKING PRESSURE (psid) lohm rate at 25 psid and greater Relief Flow Direction SCREENED .281 PRI®/ CHEK® VALVE FREE Flow Direction FLOW POINT MINIMUM CRACKING PRESSURE (psid) MINIMUM SHUTOFF PRESSURE (psid) CRACKING PRESSURE (psid) lohm rate at 25 psid and greater 0.281 PRI/CHEK Flow Curve Relief Flow Direction: Leakage at Minimum Cracking Pressure: 10 drops/minute max. Leakage at Minimum Shutoff Pressure: 10 drops/minute max. Nominal System Pressure:...