The 228BV11 is a style 228 with choke B (cross) and physical size 11. This is not definative. The definative number is stamped on a round tag approximately the size of a dime which is affixed to the carburetor body (normally the airhorn casting) with a rivet. One could compare the numbers of the two carburetors.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop