Hand crimper,for use with 11mm or 20mm crimp seals.Top-mounted adjustment knob shows directionality for tightening/loosening,sturdy construction of rugged,fiber-reinforced resin with steel reinforcement in the handles.Comfortable,lightweight,ergonomically-designed handles fit smoothly in the hand and eliminate pinching. ● Material:Aluminum,plastic ● Color:Silver,black ● Good sealing,adjustable size ● Adjustment knob doubles as an indicator that the crimp is complete ● Narrow jaws provide better vertical clearance over vials. ● Bottom handle motion allows for better control and enhanced stability of crimping jaw