King RS4012-BP5P 4.0 Race 12in 5-Tube Bypass Shock with Piggyback Reservoir

The King RS4012-BP5P is a premium 4.0 Pure Race series bypass shock featuring 12 inches of travel, designed for extreme off-road racing applications. This high-performance shock absorber combines a 5-tube external bypass design with a piggyback reservoir configuration to deliver exceptional damping control and position-sensitive tuning capabilities.

Advanced Shaft and Rod End Construction:

• Large 1.25-inch diameter shock shaft with 1.00-inch bypass tubes
• Induction hardened to 60-65 Rockwell scale for maximum rock bruising protection
• Hard chrome plated and micro-polished to 3 RMS mirror finish for superior seal integrity
• Hydraulically pressed and TIG welded rod end attachment removes external threads for exceptional strength
• Replaceable Teflon-lined steel spherical bearing mounting on both ends

Bypass Technology and Adjustability:

• Five independent bypass tubes offer position-sensitive damping control
• Each bypass stage is separately tunable with 14 turns of precise adjustment
• Heat-treated stainless steel bypass valves and springs for consistent, fade-free operation
• Compression and rebound tubes operate independently without interference
• CNC-drilled bypass ports, hand deburred and polished for optimal flow

Reservoir and Internal Components:

• Piggyback reservoir configuration with threaded end caps for high-pressure capability
• Lightweight aluminum construction aids heat dissipation and prevents rust
• Cold-drawn 2024 billet aluminum piston with optimized fluid dynamics
• Teflon bronze wear band for smooth operation
• Viton o-ring seals for high-temperature durability
• Heat-treated stainless alloy valve shims maintain consistency at elevated temperatures

Quality and Testing:

Every King shock is 100% hand-made in the USA and undergoes rigorous testing. Precision bore and hone tolerances of +/- .001 inch ensure cylindricity and optimal piston seal performance. Bypass assemblies are pressure tested to 300 PSI before plating. This universal race shock is designed for custom off-road racing applications and comes with necessary mounting hardware including washers, bushings, and nuts.

Key Specifications:

• Shock Body: 4.0-inch diameter
• Stroke Length: 12 inches
• Shaft Diameter: 1.25 inches
• Bypass Tubes: 5-tube configuration with 1.00-inch diameter
• Reservoir Type: Piggyback
• Application: Universal race (not vehicle-specific)
• Warranty: 90-day manufacturer warranty against defects