This coupler features a removable rubber pad inside the coupler which allows it to fit any tube size or Gimbal handlebar that comes with a 25mm to 30mm diameter. There are also various threaded holes including 3/8in-16 (2 pcs), 1/4in-20 (7 pcs) and M4 (pcs) on the main base to accept a wide range of adapters, grip accessories, cameras, lights, and monitor arm.