Sold Individually - For GM HD trucks with 4-5 Inches of Rear Lift Gas / Oil Separated - Eliminates Cavitation. 5/8” Hard Chrome Plated Shaft. Rebuildable and Revalvable.Two-Stage Sealing System - Dirt Out, Oil In. Nitrogen Charged Internal Chamber. Designed For Use On Leveled & Mild Lifted Vehicles. Developed For Use With Larger Oversized Wheels and Tires. Made in USA.