Air/Water Syringe button is compatible with most major manufacturers including: A-dec, Uniflow, DCI, Dentech, Proma, Ampco, and Pelton Crane. Guaranteed to work with DCI3430. Instuctions on Replacing the Syringe Button: Remove retaining pin by pressing buttons down. Use the skinny end of a metalic syringe tip or a stiff paper clip to push the pin out. Take pliers to remove the remainder of the pin. Once the buttons are removed out of the syringe, then you can return the syringe spring back into the head of the syringe. The small end of the spring should be facing outwards toward the bottom of the buttons. Place new buttons back into the air/water syringe. Hold down both syringe buttons and return the syringe pin back into the syringe.