it may have a manufacturer's (not Grady) part number on it. Try looking. If you are referring to a gas shock strut device, the important specs to match a new one are the force in pounds (usually part of the part number), the open length and the fully retracted length. Be careful if you are looking at less expensive Chinese replacements. I have had issues with them in the past and now avoid them.
Here is an example of what I am referring to:
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