OEM AP straps used a brass insert at the end of their straps so it fits flush the the plots. If you NEVER changed straps before, go with OEM AP parts only as ALL the other aftermarket options are rather difficult to install and dont provide the quality level of fit and finish. I have had some pretty poor experiences with aftermarket brands and have had a few of their straps peel near the top of the strap where the strap meets the plots and the lining is never as good. There is ONE good aftermarket strap maker I know, if you'd like his info PM me.
I know OEM AP is expensive, but WELL worth it, esp if you arent changing straps all the time.
"Don't be such a stranger my friend. I know you are busy but drop a note to a mate now and then." - Cheers Uncle Bob
**MOD edit: non OEM mention removed**