The AEROX Performance RC Mild Spring in Medium Black is a 4.0 lb/in rate shock spring sold as a pair. Wound from metal wire, these springs are designed for a mild, progressive feel suited to a wide range of 1:10 scale off-road vehicles. Each spring ships with a small rubber retaining sleeve. The medium spring rate makes these a practical tuning option for drivers looking for a balance between compliance and control. Features: 4.0 lb/in spring rate Mild wind profile for progressive suspension feel Sold as a pair Includes rubber retaining sleeves Compatible with a wide range of 1:10 scale off-road platforms 7/7/26 cs