Pearl Vision Birch Bass Drum Jet Black 22x18 A birch inner ply provides naturally equalized, punchy tone with enhanced projection and sustain Pearl's new Vision Birch Series is their most affordable 100% birch drums Ideal for live performance or studio work, Birch provides a balanced tone with low-end projection to match that of the high frequencies produced by smaller drums Like all Pearl drums, this 6-ply, 7 5mm shells feature the SST construction process which includes extreme heat, precision-cut scarf joints, proprietary Acoustiglue and over 1000lbs of hydraulic pressure