Enots 3.5 inch Roller Fuel cap.

[Wedginald]

I am wondering about the value of an Enots 3.5 inch roller filler cap. I can see that they are quite sought after for a range of classic car applications.

I have put some pictures below and would like fellow members to give me some advice about value. Apologies in advance if this is contravening any forum rules. If it is, please advise and I will amend accordingly.

I ask, as I have had an offer on it and am trying to understand whether the offer is fair.