This is the sequel to ZZP's popular 2.5" straight through resonator that we use in the Ecotec/Sonic/Cruze/and other cat backs. Our smaller version provides 75% of the drone and noise dampening of the larger resonator at almost half the size. The 3" version measures 16" end to end, with a 10" x 5.25" body. These resonators can fit in tight places and due to their triple chamber design still provide that great sounding exhaust note you've come to expect from ZZP products.