Humpback Engineering 5-string bass pickups. Purchased new in October 2025 and used for about two months. They have a clear sound with tight highs and a powerful low-mid range! The string spacing at the bridge is about halfway between 18mm and 19mm. I'm selling these at a lower price because I bought them before the price increase. 【RF-J Series】 ・The number of turns in the coil is kept low to ensure a rich harmonic content. ・The wiring and solder are tuned to provide a thick low-mid range and excellent response. ・Although the number of turns is low, the volume is substantial. ・The sound of the pull when slapping, and the sound of the neck pickup alone are points you should definitely try.