Made in the U.S.A
The other factor to consider here is - all grade 8.8 and 12.9 bolts are coming from China.
You really do have to ask yourself...are they really undergoing continuous quality control in terms of yield tensile strength? Most people will realise ARP are
This is the very reason Motorsport and performance applications use and trust ARP
50mm pack is for Perentie & Counties which run the 5806 Flange - Everything uses the 45mm pack