What are the names for the strips in doorways joining carpets/laminate/etc?

[d000hg]

Our doors are too wide for the standard 900 strips so I want to find some online. But I can't recall what they're called... and how you distinguish between those for carpets on both sides, and those to join carpet onto laminate, or carpet onto solid wood; do they have different names?

We have a carpet on thick underlay in the hall, dropping down about 1cm onto our newly refurbished solid wooden floor in the bedroom. It was previously carpet on both sides so clearly I need a new strip - what is this called and any recommendations where to source an overly long one?

Thanks.

 

[freddiemercurystwin]

Door threshold, amongst others. Longer ones to cut down as required are widely available in many retail outlets both trade and for public and online.

 

[d000hg]

Is "zig-zig" what I want? Trying to figure out how the step-down part works - is something like this able to be bend flush? https://www.screwfix.com/p/zig-zag-door-strip-gold-effect-0-9m-x-42mm/56002

I hadn't expected it to be hard to source, but my handyman said they went to several stores to no avail. Since our giant B&Q halved in size anything like that is a PITA to sort.