King RS4020-BP4H 4.0 Pure Race Bypass Shock 20" Stroke 4-Tube Hose Reservoir

The King RS4020-BP4H is a Pure Race series bypass shock engineered for extreme off-road racing applications. This premium shock absorber features a 4.0-inch body diameter with 20 inches of travel, combined with a 4-tube bypass configuration and hose-style remote reservoir for maximum performance and adjustability in the most demanding conditions.

Advanced Bypass Technology:

• Position-sensitive 4-tube bypass design allows independent tuning of each stage
• Compression and rebound bypass tubes operate independently with no cross-influence
• Precision bypass valves with 14 turns of adjustment for fade-free operation
• Heat-treated stainless steel bypass valves and springs for consistent performance
• Large 1.0-inch diameter bypass tubes maximize flow in a compact profile

Premium Construction:

• 1.25-inch diameter shock shaft induction hardened to 60-65 Rockwell scale
• Hard chrome plated and micro-polished to 3 RMS mirror finish for superior sealing
• Precision-bored shock tubes held to +/- 0.001-inch tolerance for optimal piston seal
• CNC-drilled bypass ports hand-deburred and polished before aircraft-quality TIG welding
• Cold-drawn 2024 billet aluminum piston with optimized port designs
• Teflon bronze wear band provides smooth operation and extended service life

Race-Proven Design:

• Threaded reservoir end caps withstand higher pressures and simplify maintenance
• High-strength heat-treated adjustment screws resist bending and breaking
• Replaceable Teflon-lined steel spherical bearings at both mounting points
• Pressure tested to 300 PSI before final assembly
• Fully rebuildable and serviceable for long-term performance

Hand-built in the USA for professional racing teams and serious off-road enthusiasts, the King RS4020-BP4H delivers unmatched control over high-speed and low-speed suspension oscillations. Each shock is custom-configured to your specific application requirements.