Thick steel body - Most quality gun safes are constructed with 8- to 10-gauge steel.
Door construction - The safe door should have an armor plate or solid steel plate, which can protect the door from power tools.
Security rating - The gun safe should have at least a B-rating to protect your weapons from theft. For protection against hand tools or power tools, you have to get a gun safe with a TL-15 rating or above.
Fire rating - Gun safes with a 1-hour fire rating or higher can provide your guns with adequate protection during fire emergencies.
Lock - Choose a gun safe with a UL-listed lock.