16/10/2026
Not sure which size you need? Don’t worry — it’s actually pretty simple.
There is a little bit of overlap between the Regular and Jumbo sizes, so if your gap falls somewhere in that middle range, you’ve got a bit of flexibility.
Regular: suitable for gaps from 2–22 mm
Jumbo: suitable for gaps from 12–35 mm
If you’re unsure, grab a standard UK £1 coin and stand it on its edge. At 23.43 mm, it gives you a really handy quick reference:
Coin won’t fit? You’re looking at a smaller gap, so Regular is likely what you need.
Coin fits underneath? Your gap is around 23 mm or more, so Jumbo is the way to go.
And if your gap happens to sit in that 12–22 mm overlap, either option may work — it just gives you a little choice depending on how much coverage you want.
No complicated measuring required — just a quick check and you’ll have a much better idea of which size is right for your door.