Chapin 6-5369 Relief Valve, Acid Staining. The great thing about Chapin sprayers and accessories is the ability to repair anything with their huge selection of parts. Chapin makes high quality products that will last for years of use. Purchase a new sprayer or repair your old one. Fits Chapin Sprayers: 22230, 22240, 22350, 22360, 2658, 2659 and 2660.