Bring race technology to your adventures with Old Man Emu's BP - 51 Suspension system, featuring revolutionary patent - pending technology developed to deliver unparalleled on and off road performance. For use on coil over models, BP - 51 employs high - quality X5K grade steel coils that incorporate application - specific design. Because they are engineered, developed, tested and manufactured entirely in - house by the Old Man Emu team, ARB can guarantee the highest possible quality. All Old Man Emu Suspension systems come with a 3 - year warranty.