Our updated quadrafone upright bass pickup offers four 20mm sensors offering the player to optimize string balance and tone. We hand craft all of our pickups to specific standard and offer life time warranty. We are a young grass roots company based in Milwaukee County. Contact us if you would like a custom build otherwise we will send you our standardized model. We do not usually include adhesive for fastening the elements to the bridge (we will on request). We recommend using double sided tape or dab of superglue once the optimal placement for your instrument is found.