RockJock's 4-inch lift rear coil springs that are included in our JK 2 or 4-door Johnny Joint® suspension systems are a dual rate with a combined rate of 88lbs. and a free length of 18.55". Gloss black powder coated finish. In heavily loaded or and/or hard top 2 or 4 door applications, these springs may not provide a full 4" of lift. In this instance, see our CE-9132R1 spring for a little extra height boost. Additionally, combinations of these springs may be used to address vehicle lean issues. If you need help choosing the correct springs for your Jeep - just call the RockJock sales staff!