On the high st (or at least in a physical local shop). And what’s it called?

What size ?

Is there a clas Olsen near you?

Flexible hose – should be found at builders’ merchants, especially plumbing specialists. What diameter and length?

The external diameter of the joining piece is about 24mm or so.

I can apparently buy 45m of it from Screwfix..

Clas ohlson – if we end up in town tomorrow I might try there.

That looks like 25mm flexible conduit or a washing machine waste pipe.

ribbed pipe like that is usually used for anything that involves suction. Depending on the size you could butcher an old hoover maybe. Not on ‘the high street’ but in local trading estates anywhere that deals with dust extraction perhaps or the suction pipe for water pumps. Machinemart do various pumps for water so might have something. A garden centre that has ponds and fountains maybe at a stretch

You can get washing machine/dishwasher discharge hoses from any plumbers merchants. Usually 1.5 or 2.5 metres.

Pond supplies sell this kind of stuff by the metre.

Electrical wholesaler, it’s flexible conduit in 20 and 25mm