Here's a pickup I made for my double bass. It can only be attached to a bridge with adjusters. It's for a 6.5mm shaft. I think the sound is well-balanced. If you use it with a type that goes under the bridge, you can switch between them depending on the venue. Please secure it to the tailpiece with the included cable ties, etc. It's new, only tested for functionality, and has a handmade feel. Thank you.