3/4" ID Reinforced Silicone Coolant / Vacuum / Air Bypass Cap with Clamp

Product Description:
High-temperature reinforced silicone cap designed to seal coolant, water, air, and vacuum ports in automotive and performance applications.
Ideal for replacing rubber caps or blocking unused ports where heat and pressure resistance are required.

Constructed from 3-ply polyester-reinforced silicone, this cap provides superior durability and leak resistance compared to standard rubber caps.
Suitable for OEM replacement, performance upgrades, and custom installations.

READ FIRST – IMPORTANT FITMENT:
Inside Diameter (ID): 3/4" (19mm)
Always measure hose or port outside diameter before ordering.
Not compatible with fuel, oil, or petroleum-based fluids.

Specifications:
Product Type: Reinforced Silicone Cap
Inside Diameter: 3/4" (19mm)
Outside Diameter: 1-1/16"
Wall Thickness: 4mm
Inside Length: 1-1/2"
Reinforcement: 3-Ply Polyester
Temperature Range: -58°F to 375°F (-50°C to 200°C)
Color: Black with green layer
Clamp Included: Yes (Black Stainless Steel)

Features & Benefits:
Handles high temperature and pressure
3-ply reinforcement prevents swelling and cracking
UV and ozone resistant
Secure clamp-on installation
Long service life in demanding environments

Common Applications:
Coolant system ports
Water and heater core lines
Vacuum and emissions ports
Throttle body water ports
Turbocharger bypass ports
Air intake and pressure testing
Custom automotive and industrial builds

What’s Included:
1 × 3/4" reinforced silicone cap
1 × black stainless steel clamp

Shipping & Trust:
Free shipping with tracking included
Ships fast from California warehouse
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