New filler valve rather loud. Any ideas?

[honoursword]

Morning all hope all is well.
I recently needed to fix our leaky main bathroom toilet. I thought as I am taking the cistern off the wall I'd replace all the parts so I wouldn't have to worry about it for a few years at least.

I installed a new flush valve and a new filler valve. Both work fine but the filler valve is a lot louder filling the tank than the previous one.

I installed a
The water drops down from the blue filler on the top and I recall that on the previous filler valve there was a plastic sleeve that sort of muffled the fill. However this valve never came with one.

What are these sleeves called? Can I buy them separately of the valve? I cannot seem to find them anywhere.

Help would be appreciated.

 

[snowhead]

Restrictor is what you need.
It's needed if the water supply at the WC is mains pressure.
There should have been one with the new fill valve.

There's sometimes 2 one with large gaps for low pressure and one with small gaps like below for high pressure