As title, bought in error off ebay. Still in packaging, will only fit ST170.

£45 inc postage

That's worried me. I used blacktop zetec bolts in my ST.
Can you tell me what the ARP part number is please?

My understanding is that these are are too short to fit my blacktop but are the correct length for a ST170. I presume that the blacktop ones would fit the ST170 but would be longer than they needed to be. I will check the product code later.