Fire extinguisher just been serviced. Is it normal?

[Zoobeef]

I've just got my fire extinguisher back from servicing. It's a lifeline Zero 2000 one.
When you roll it in your hands you can hear something scraping round the bottom and if you shake it it rattles from side to side. If you turn it upside down the noise stays at the bottom.
I don't remember it ever doing this when I installed it originally 2 years ago and when I took it off 2 weeks ago to post it. So is it normal? Something to agitate the insides?
I've emailed the place for confirmation but I'm guessing they won't be open until Monday so I can't reinstall it until next week.

Many thanks.

[V8 FOU]

It's the pick up pipe. Means that it will pick up the stuff regardless of position.

[Zoobeef]

Cheers, I thought they were fixed.
Had a reply from a mate though and he said they use a flexible one now instead of the old fixed ones.
Happy days, I don't need to worry!