38521 - O-ring $2.25 SKU 38521 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart This item is a recurring or deferred purchase. By continuing, I agree to the cancellation policy and authorize you to charge my payment method at the prices, frequency and dates listed on this page until my order is fulfilled or I cancel, if permitted. Part # 38521 is the back up o-ring for JD9 spray guns.