Please help shower fitting what is this piece

[Fairgroundride]

Trying to fit new shower these little round mesh things are in the ends. I can fit it with them in place, but it’s very hard. The instructions make no mention of them at all & they don’t feature in the video I watched. Am I supposed to remove them?

Apologies any advice gratefully received

They look like filters to me.

Something like this...

https://www.aqualisa.co.uk/bar-valve-inlet-filters-pair.html?gclid=CjwKCAjw-IWkBhBTEiwA2exyO_eMmB_decQJ1HBbN7ZsHj6n2rsxbQRIzZvgOHz94SrbnC0s47xFSBoCVw8QAvD_BwE

Yes they are filters. Water can contain large clumps of stuff. Get it caught in the wrong place and it can very suddenly change water pressure that can cause it to go very cold... or very hot. They are important.

So we should leave them in? It’s so weird,they aren’t in any of the pictures & not visible in the video.I wonder if we’ve somehow ended up with them the wrong way up? I’ll try turning them over.

Yes they should be there. I've not seen one that shape exactly before, but every shower fitting has them. Mine have always been flat filters, but much the same thing.

I will go back & have a little fiddle about, I did manna get to get the threads to catch & got the bar on, but I had to lean my whole weight on it to get it close enough. In the videos they just screw it on practically with one finger.