Product Description 3700 series recessed mounted 4C parcel parcel locker is manufactured by Salsbury Industries to USPS-STD-4C specifications. Ideal for apartments, commercial buildings and residential developments. The 4C parcel locker is constructed of heavy duty aluminum and stainless steel hardware. Feature a durable powder coated finish available in aluminum, bronze, gold and sandstone. Fit with a 2 key security system that allow tenants a convenient way to receive packages on site. U. S. P. S. standard 4 C requires a minimum on 1 parcel locker for every 10 tenant compartments. Available in a front loading or rear loading unit. From the Manufacturer Salsbury 3700 Series 4C Horizontal Mailboxes - Rear Loading - U.S.P.S. Access are ideal for apartments, commercial buildings and residential developments. 4C horizontal mailboxes are U.S.P.S. ApprovedRequired for new construction and major remodels. U.S.P.S. standard 4C requires a minimum of 1 parcel locker for every 10 tenant compartments. For indoor or outdoor use. Constructed of heavy duty aluminum and stainless steel hardware. Feature a durable powder coated finish available in aluminum, bronze, gold and sandstone. Doors include a heavy duty cam lock with a dust/rain shield and 3 keys. MB1 doors are 13-1/4'' W x 3-1/4'' H, MB2 doors are 13-1/4" W x 6-3/4" H, MB3 doors are 13-1/4" W x 10-1/4" H and MB4 doors are 13-1/4" W x 13-3/4" H. Available in three (3) MB1 equivalent door high units to fifteen (15) MB1 door high units. The popular maximum high (56-3/4"H) units are also available. ADA compliance guidelines. Available in configurations that are 1 door wide (single column) and 2 doors wide (double column). Fully integrated and stand-alone parcel lockers are available in 5 MB1 door heights (PL5 - 17-1/4" high) and 6 MB1 door heights (PL6 - 20-3/4" high). Salsbury Industries is an ISO 9001: 2008 certified company and has excelled in the field of manufacturing since 1936.