Polycarbonate Helmets?

Indeed, but Momentum = mass x velocity, hence p=mv

 

What @Hughdg said, I have experienced that too.

I think its like the MOT, once it leaves the shop there is no liability. If they were that bothered how would they allow them on ebay for a tenner.

I just wouldn't rely on the ACU sticker as a sign if quality.

TB

 

If they ACU use SHARP then why do you need a sticker it just reinforces my point about revenue for ACU.

 

An interesting read

https://www.motolegends.com/why-we-do-not-rate-the-sharp-helmet-test

 

And acknowledging other bikers ist verboten!