DOOR-MOUNTED BOX: Install this spacious mailbox on office or house doors with a thickness of up to 1.75 inches. Cut out a rectangular shape and refer to the manual for easy installation. (Note: This secure drop box is not intended for wall mounting.) AMPLE STORAGE CAPACITY: Our door drop box boasts dimensions of 9.75''(L) x 4.25''(W) x 14.75''(H), providing abundant room to accommodate your mail, documents, checks, envelopes, as well as small items like keys and cash. It seamlessly fulfills your everyday storage requirements. STURDY MATERIAL: Made of heavy duty 1.2mm steel, this metal locking mail box is not only long lasting, but also provides great protection for your mail, letter, envelope, money, check, and night keys for business office. UNIVERSAL DOOR FIT: Our lockable cash drop box is designed to effortlessly attach to wooden doors with a thickness of up to 1.75 inches, ensuring convenient access from both front and rear sides. SECURE ANTI-THEFT: Our deposit safe features a robust anti-fishing design, ensuring top-tier security. This slot-equipped dropbox safe is exclusively accessible using the designated key, and is impervious to forceful attempts at prying it open. BUILT TO LAST: Crafted from rustproof galvanized steel plate, this lockable deposit box is engineered for exceptional longevity. The powder coating finish not only enhances its durability but also ensures the longevity of your mail slots for doors.