Salsbury Industries 3390 Standard Replacement Lock for F Series Cluster Box Unit Door with Three Keys Go to amazon.com Related posts The 13 best mailbox lock replacement for 2022 FeatureStainless SteelAvailable for commercial mailboxes and residential mailboxesCorresponding key blanks (box of 50 keys) are available DescriptionSalsbury Standard Replacement Lock - for F Series Cluster Box Unit (CBU) Tennant Door with Three (3) Keyed Alike Keys Per Lock.