Diaphragm 0278240 Gun_G10 Wagner recommends replacing the piston

Wagner recommends replacing the piston & spring if the sprayer takes longer than 15 seconds to prime when well lubricated

just make a note in the comments section of the order

Features: Flexible - makes it easy to insert into 1-gal and 5-gal pails

Twin Hose Desing means no duct-tape or Zip-Ties needed

twice as fast

Diaphragm 0278240 Gun_G10 Wagner recommends replacing the piston0278240 Includes: Diaphragm spring, oval spacer, membrane, and nut; as shown in picture. This "0278240 Green diaphragm" replaces the older "0288771 White diaphragm" and "0270201 Red diaphragm" . Fits the Following Series Pumps:(but not limited to) All Wave Series Diaphragm Pumps, 404+, 425, 505, 525, 650, 655, 830, 831, 833, 834, 835, 836, 838, 1050, 1150 Pro Gold: 841, 844, 848, 850 And more! Very common diaphragm for Wagner and SprayTech. Check your