x series signature david ellefson concert bass cbx v mj series with a speed neck contour 2910134539 with a speed neck contour the 12" 16" compound radius amaranth fingerboard creates the ideal playing surface for fat riffs and easy chording near the black plastic nut while gradually flattening in the upper registers for lightning quick solos and wide bends without fear of fretting out Redesigned ergonomic contours provide the perfect platform for launching a musical assault the upper contour provides a comfortably stable anchor for pick or fingerstyle playing alike while the lower contour provides perfect balance when propped on a knee for monitor stands Designed in conjunction with one of the founding fathers of thrash metal highly acclaimed bassist David Ellefson of Megadeth the X Series Signature David Ellefson Concert™ Bass CBX V is a beast of a bass