The Pearl Demon XR Double Bass Drum Pedal is your direct path to rapid fire bass drum performance. The product of a two year research and development collaboration with drummer Gorge Kollias the Demon XR (for Extreme Rebound ) essentially rewrites the playbook on high-speed bass drumming. Featuring a stripped-down machine shop design for lightweight feel and a faster stroke its secret lies in the enhanced rebound action of the XR High-Tension Spring.