How to tell if REV A or B without seeing Package

[HP67]

Most of the Amazon ads have the product info listed pretty clearly.

For example:

Brand Name HP
Item Weight 8 ounces
Product Dimensions 7.2 x 3.4 x 0.6 inches
Item model number NW280AA
Number of Items 1
Manufacturer Part Number NW280AA

So with a little checking and perhaps an email to verify the correctness with the seller, you should have your answer.

Alternatively, you could search TAS and Flamazon with the G8X92AA part number Miguel referenced.