differences between HWIC-AP-AG- A vs B ?

[nacholariguet]

I'm needing one for an 1841 and it's not clear which one; both targets the american standard, sure; can anybody tell me ? Is B a revised and newer edition ? Do A have some incompatibilities with latest IOS or hardware glitches anybody knows of ?

[didyap]

The A version models (designated in the product number) are being replaced, and customers are encouraged to migrate to the B version models. The new models are fully compliant with FCC regulations for operations in the 5 GHz UNII-2 band. Migration to the new models is required to meet FCC wireless specifications that become effective in July 2007. Customers with existing products can continue to use their equipment.