Section 17290 Of Division 2. Definitions From California Penal Code >> Division 2. >> Title 1. >> Part 6.
17290
. As used in this part, "undetectable knife" means any knife
or other instrument, with or without a handguard, that satisfies all
of the following requirements:
(a) It is capable of ready use as a stabbing weapon that may
inflict great bodily injury or death.
(b) It is commercially manufactured to be used as a weapon.
(c) It is not detectable by a metal detector or magnetometer,
either handheld or otherwise, which is set at standard calibration.