The sound button for violin and viola
The BENDER button for violin and viola has a fine thread machined on the cone surface. The thread increases the area of contact between the button and the instrument. Instead of just being push-fitted, the BENDER button is screwed into the bottom block. The tight fit allows for perfect sound transfer between tailpiece and instrument.
The BENDER buttons are precision milled from solid aluminium. The higher mass, compared to regular wooden cones, adds to the sonic improvement.
The black anodized aluminium button is antiallergic.