• optimal screw locking during the active treatment phase
• built-in stops prevent the screws from coming apart once maximum expansion has been obtained
• reliable activation/deactivation of the screw with clearly perceptible click after a 1/4 turn
• no accidental turning back when pulling out safety key during activation
• minimal dimensions with maximum expansion range
• permanently laser-marked arrow on the body of the screw indicates the opening direction and max. expansion

Packs (1 piece / 50 pieces) with 1 safety key, pack (10 pieces) with 10 safety keys.