S1 Door Type Features: 3mm steel panels, lightweight, single locking bar. Advantages: Reduced weight makes them easier to use than shipping container doors. The door plates are fabricated from 3mm steel. This is thicker than is used for standard container doors which enhances security. Recommended for: Storage containers for schools, clubs and domestic storage, where you require frequent use and ease of use is essential. S2 Door Type Features: Original shipping container cargo doors, corrugated steel panels, external rubber seals and four locking arms. Advantages: Excellent security and guards against all forms of water ingress without the need for extra modification. Recommended for: Heavy duty storage, especially construction sites, or where access is required less frequently. S3 Door Type Features: Steel panel doors, lightweight, two locking arms, external rubber seals. These doors are unique to Containers Direct! Advantages: Reduced weight makes them easier to use. Combines the best features of S1 and S2 door types. Recommended for: Storage of items easily damaged by moisture e.g. paperwork, fabrics, furniture and for frequent use. For more details, please see our types of shipping container doors page.