18004404CM (40DHD) by PT-Coupling | Heavy Duty Cam & Groove Adapter | Type DHD | 4" Coupler x 4" Female NPT | Ductile Iron | Buna-N SealFeatures & Applications: Excellent abrasion and wear resistance. Good strength and toughness characteristics. Ideal for use with sand, grout, cement, and other abrasives. 2 1 2" and smaller couplers come standard with 2 cam arms while 3" and larger couplers come with 4 STA LOK II cam arms. Made in the USA Part Name Item # Heavy Duty Coupler Female NPT Thread Max. Allowable Working Press. (PSI)* 15DHD 68781500 1 1 2" 1 1 2" 500 PSI 20DHD 68782000 2" 2"