Fluidmaster Mystery - Rubber Corkscrew

Was having very low waterflow issues with a Fluidmaster toilet valve. When I disassembled it, I found a white approx. 1" rubber corkscrew object with a metal "washer" on one end loged in the lower part of the valve body.

Any ideas on what this is and if it's supposed to be in the valve body? I ended up prying it out with a screwdriver and the waterflow is great now. If it is not part of the valve assembly, I'm not sure how it got there since it wider than the water inlet.

Its a flow control device. I think it is there to get the water spinning as it travels up the valve. Best one to answer that question is the ones how designed it.

But often when I get a flow problem with a fluidmaster valve,
I replace the black diaphragm under the top cap.
The neoprene diaphragm swells up and restrict the flow

Mr_David said:

Its a flow control device. I think it is there to get the water spinning as it travels up the valve. Best one to answer that question is the ones how designed it.

But often when I get a flow problem with a fluidmaster valve,
I replace the black diaphragm under the top cap.
The neoprene diaphragm swells up and restrict the flow

Click to expand...

Yup, Mr. David has it. flow restriction device. Helps prevent water hammer from damaging the fill valve.