Frequently Asked Questions

No, Lockdown is the taller model so it doesn't require extensions.
No, the spacers can improve performance but DoorJammer was designed and tested without them.
Yes, as long as the strip does not prevent DoorJammer fitting under the door. Crushing or damage to the strip could occur, however.
Yes, DoorJammer's PAS24 certificate was issued at full extension. You can see it in action in the video here.
Yes, DoorJammer works just as well!
You will need a minimum of 3mm to fit DoorJammer. The maximum gap for DoorJammer is approximately 33mm and for Lockdown, it's 42mm.
We demonstrated DoorJammer to fire service professionals who agreed it would not prevent them from breaching a door by its hinges. UK Police liked it so much we're a preferred product through Secured By Design.
Yes, DoorJammer is TSA-friendly, compact and lightweight.
When fitted firmly, DoorJammer should remain in place, however the extension foot provided has a special grip that helps for very thick carpets.
DoorJammer requires a minimum 3mm gap under a door to fit - most uPVC doors do not have this gap.
DoorJammer only weighs a little more than a mobile phone at just 210g / 0.46lbs and Lockdown is 810g / 1.78lbs.
Sorry! DoorJammer and Lockdown are both painted in highly-visible Classic Red.
The foot will extend DoorJammer by 11mm.
We only use high-grade steel to achieve DoorJammer's incredible strength. Smaller parts and accessories are rubber and plastic.
We do not recommend this. DoorJammer is designed with a quick-release function for safety and portability.
No, currently outswinging doors are not compatible with DoorJammer.
Yes, we do accept a limited amount of distributors - apply by emailing us at