1. a) Type 3 magazines shall be constructed according to the following specifications or to any of the specifications listed in Section 200.500 of this Part which is practical.

   1. 1) A type 3 magazine is to be constructed of not less than number 12 gauge (.1046 inches) steel, lined with at least either ½-inch plywood or ½-inch Masonite-type hardboard.
   2. 2) Doors must overlap sides by at least one inch.
   3. 3) Hinges and hasps are to be attached by the welding, riveting or bolting with the nuts on the inside.
2. b) Type 3 magazines shall be equipped with at least a five-tumbler steel padlock having at least a ⅜ inch-diameter case hardened shackle.

A Type 3 magazine shall be a portable structure that is fire-resistant, theft-resistant, weather-resistant, and ventilated.