Note: All custom finger buttons orders are non-refundable. A few brass instrument manufacturers may have poorly machined valve stems, which may cause an alignment issue with our finger buttons. This can be corrected by shimming the threaded union between the piston and stem to be true. If this is not corrected, the stem may be out of round on the button end causing a collision with the top cap. Harrelson top caps usually provide more space to prevent this issue. Brands to have this problem include BAC, Getzen, Edwards, Bach, Conn, ACB and Adams. All Harrelson trumpets built before 2012 will require new SWE Top Caps to use any of our Finger Buttons.