NT Quick Return cutter / knife has a revolutionary double spring-retractable and ratchet wheel blade locking mechanism that gives this cutter highly safe cutting features. The mechanism is activated by a powerful return spring that retracts the blade the instant the user release the thumb from the slider, so the blade remains extended only while cutting, eliminating the possibility of injuries. And the ratchet wheel blade locking mechanism prevent blade for slipping. Besides, it has other features like an Extra length for jobs requiring extra "reach". The design also includes a strong ergonomic metal grip, auto-lock mechanism, heavy gauge stainless steel blade channel, blade snapper, rope loop and an anti-slip handle. Uses replacement blades: BL-150P. Pack 10pcs. Master 100pcs.