Size 12 x 12 x 18.5": (HxWxD) locking mailbox holds 2-3 days of mail. Easily accessed by mail carriers and delivery drivers, our post mount mailboxes for outside receive small and large envelopes, poly-bag style mailers and packages up to 16 x 10 x 2. Receive What You Buy: Prevent identity, mail and package theft. Stop porch pirates with our locking mail boxes for house outside. This post mounted mailbox features an anti-phishing panel and anti-pry latch. Keep out sticky fingers with Adoorns mail box. Easy to Mount: Combine Adoorns residential mailboxes for outside with our adoorn post for mailbox (sold separately) or use your existing post. This mailbox has five different hole patterns to accommodate most posts (Not compatible with the post called Mail Boss 7121 which Amazons algorithm continues to incorrectly recommend..uggg!). Our outside mailboxes can be installed quickly and easily. Instantly Add Curb Appeal: Adoorn's outdoor mailboxes are designed to compliment home decor. This ocean blue mailbox includes a bright red mail flag for added charm. Our modern mailbox comes in a range of eye-catching colors. Durable and Weatherproof: Our locking mailboxes are constructed from heavy-duty galvanized steel, stainless steel hinges and rust proof finish. This metal mailbox protects from rain and snow. Chicago based small business. We are here to help answer any questions you may have!