Durable steel cabinet houses restricted door key. Place by locked exit door, storeroom with emergency equipment, etc. Key is accessed by breaking glass with hammer which is attached with a chain to the key box. Glass is easily replaced. Key box`s bright red finish is easy to spot. Size: 6-3/4"W x 6-7/8"H x 2"D. If multiple boxes are needed using the same key, specify keyed alike option.