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H300-16 Horizontal Letter Box

Recommended for apartment blocks, commercial buildings and student accommodations, the H300-16 Secure horizontal post box is an EN13724 approved mailbox for indoor and outdoor applications. Extremely capacious despite its compact dimensions, it has a total capacity of just over 18.5 litres within dimensions of 300 x 165 x 375mm (width, height, depth). Large enough to accommodate A4 size documents (C4 envelopes) without bending, these space-saving units can be banked together or installed individually.


    The H300-16 Secured by Design mailboxes are hard to surpass when it comes to versatility. The can be installed individually, although they are most commonly used to create a mailbox bank with anything up to 200 units and more. Post Boxes UK offers an integrated service including planning, drawings, delivery and installation, with no job too big or small. Contact us for a personalised proposal.


    Wall mounted, wall recessed, and freestanding installation options are available for the H300-16 horizontal mailbox. Freestanding units are supplied with support legs.


    To meet UK Building Control and Fire Regulations, the H300-16 secure letter box is available with Class 0 Flame Retardant and Fire Spread resistant paint options. We currently have over 200 RAL colours to choose from, along with a range of high-end finishes including gloss copper, black chrome, and satin stainless steel.


    Post Boxes UK offers a standard turnaround time of 4 weeks for bespoke mailbox banks. This depends on the size of the project and the complexity of your chosen design. We endeavour to meet all deadlines and welcome you to contact us for up-to-date information on lead times.

SKU: H300-16

  • Material
  • Finishing Surrounds
  • Support Legs
  • Numbering / Identificiation
  • Locking Options
  • Replacement Keys / Locks
  • Security
  • Model Range

The H300-16 communal post box is constructed from 1mm electro-galvanised steel or stainless steel. It is rust, corrosion and weather resistant, and ideal for both indoor and outdoor locations.

Post Boxes UK offers a variety of finishing surrounds to give the H300-16 Secured by Design letterbox a polished and professional look. For wall recessed post boxes, we offer a choice of 20mm and 40mm recess trim surrounds, with larger dimensions available upon request. For wall-mounted and free-standing multiple-occupancy mailboxes, we recommend either 2mm sheet finishing surround or 20mm volume finishing surround, depending on the project.

Where wall space restrictions require that freestanding letterboxes be specified, Post Boxes UK offers a range of support legs for the H300-16 lockable mailbox. These include side support legs, pedestal support legs, and combinations for larger mail banks. Please note: to conform with EN13724, your bank of letter boxesshould not exceed 1800mm in height.

Post Boxes UK offers a full mailbox customisation service. We can personalise your H300-16 post boxes with apartment numbering, engraved nameplate inserts, laser etched identification codes and much more. Our mailboxes offer multiple customisable areas, and we have almost every Microsoft Windows font available.

A Eurolock Cam Lock is included with every H300-16 post box. Should you require a more comprehensive security system, Post Boxes UK offers a variety of robust locking solutions such as push button Digi-locks, master keyed suites (UMK), Salto compatible locks, and RFID/NFC proximity locks. Please contact us for more information.

Should you require replacement keys for your H300-16 multi-unit letterboxes, please contact Post Boxes UK. We can provide any number of spare keys and replacement locks for your management teams, with bulk orders qualifying for a discount.

Secured by Design letterboxes such as the H300-16 are designed to comply with the police initiative outlined in the Homes Guide 2016. They include anti-fishing devices to prevent tampering and unauthorised access, and they are fully compliant with British Standard EN13724 for your peace of mind.

Mailboxes in the H300 range are sleek, streamlined and sophisticated. The H300-16 offers a lower profile height of just 165mm, yet it has a high capacity and can easily accommodate A4 size documents without bending or folding the envelope. A great choice for commercial offices, communal reception areas, and apartment blocks, they provide a secure solution for postal delivery.

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