Help Identifying Pickup

[Deez]

Hello new user here. Thanks for the add.

I have an old 80's or 90's Seymour Duncan pickup I'm trying to identify. Pretty sure its a JB, but the label is really worn and hard to read. It looks like it says JB5M? Not sure what that means. I've searched the Forum and Goggle without any luck. I thought Id ask you experts. It measures 16.69k with my meter. 4 conductor.

 

[jeremy]

looks like a jb to me

 

[Artie]

The "M" means it was wound by Martha Cameron. Not sure what the "5" means unless they designated A5 magnet back then.