There are 2 versions of seal BF0073 that I know of, I ship 1 of each per order.
And All the O-rings for newer nailers
for make: Senco
for models: SKS SFN1
O-ring and seal bf0073 kit, No other parts or nailer.
NOTE: Leaks from the exhaust of these nailers are usually due to the valve/cap being bad,
the only fix is replacing the valve.
O-rings will not stop the leak.