Introduced in 1997 the Modulus Flea Bass (FB4) is a 4 string bass with an alder body and carbon fiber bolt on neck. The FB4 was designed in collaboration with Red Hot Chili Pepper's Flea. This model was also available with various pickup options including Basslines by Seymour Duncan MM, Bartolini MM pickup (with NTBT active EQ) or Lane Poor MM4. Also available as the 5-string FB5 model. 34” scale 4- and 5-string models. 22 fret bolt-on carbon fiber neck with 2-way adjustable relief system. Choice of composite or wood fingerboard. Alder body. Optional exotic wood tops. Big Flake, metallic and solid color options. Flea J4 and J5 models feature Bartolini J pickups or optional Villex passive pickup system with 2 x J-style pickups and flexible passive tone shaping.