USA
The security level of anti-theft locks is divided into Grade A, Grade B and Grade C according to national standards.
1. Grade A lock cylinder, preventing technical opening ≥ 1 minute, anti-drilling ≥ 10 minutes, anti-sawing ≥ 5 minutes, anti-prying ≥ 10 minutes, anti-pulling ≥ 10 minutes, anti-impact ≥ 10 minutes.
2.B grade lock cylinder, prevent technical opening ≥ 5 minutes, anti-drilling ≥ 15 minutes, anti-sawing ≥ 5 minutes, anti-prying ≥ 15 minutes, anti-pulling ≥ 15 minutes, anti-impact ≥ 15 minutes.
3.C level lock cylinder, to prevent technical opening ≥ 10 minutes, anti-drilling ≥ 30 minutes, anti-saw ≥ 30 minutes, anti-prying ≥ 30 minutes, anti-pulling ≥ 30 minutes, anti-impact ≥ 30 minutes.
Classification
Grade A: The key is flat or crescent type, with a row of concave keyway on one or both sides or convex keyway on four sides of cross type;
Grade B: Keys of flat or crescent type with two rows of concave keyways on one or both sides or cylindrical type with multiple concave keyholes;
Grade C: Keys of flat type with two rows of concave plus S-shaped keyways on one or both sides, or double serpentine keyways inside and outside;
