• optimal screw locking during the active treatment phase
• built-in stops prevent the screws from coming apart once maximum expansion has been achieved
• 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
• small dimensions with maximum expansion
• laser-marked arrow on the body of the screw indicates the opening direction and maximum expansion

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