Ultrasonic inserts remove even the most tenacious debris, but they can be delicate. The stack should be straight for optimal vibration, and tips need to keep their original shape for superior effectiveness. Get protection for your insert and peace of mind that your insert will function optimally each and every time with the new Hu-Friedy Ultrasonic Kit featuring a Swivel Direct Flow™Insert. Includes: (1) UI30SD100 (Swivel Direct Flow™ Inserts, #100 Thin) (1) IM30HU7 (Black Small Signature Series® Ultrasonic Insert/Handpiece Cassette)