Ultrasonic Punch Horn by Sharpertek. Ultrasonic Punch Diameter 3" Titanium with either Chrome or Carbide coating options. Ultrasonic punch frequency is 20KHZ With Blow Off feature. Blow off feature connects the horn to a 1/16 NPT push to connect fitting used to blow off the punched disk out of the horn. Part Number: HP-3-20KHZ-TI-BO-TI. Other shapes such as square and oval are available upon request.