These are the sealing washers at your fuel rail inlet (or pulsation damper). You should install new ones when removing the fuel to the rail. You don’t want fuel leaks. That means fire. Fire isn’t something you want under your hood.

Sold as sets, just let me know what year your truck is at checkout.

for 1984-1988 with pulsation damper, there is one BIG one and one small one

for 1989-1995 uses 2 of the same size for the banjo bolt (there is no pulsation damper for these years)

So these are small and lightweight and minimum Priority mail shipping is $. If this is all you are ordering and can wait an extra couple days, let me know in the notes field at checkout and I can ship USPS first class and I’ll refund some of your shipping $.