Buying the HPS 9/16″ (14mm) ID, 1-5/8″ Long Black Silicone Reinforced Coolant Cap For Bypass Heater Vacuum Valve Water Port should be simple, so here are the facts without the marketing noise.

Petroleum contact requires the correct lining, so fuel and oil routing needs the right specification. Measure inner diameter at the fitting rather than estimating by eye.
Ordering the long black silicone reinforced coolant cap takes a minute and the confirmation reaches you straight away.
Our team knows the long black silicone reinforced coolant cap well, so ask if anything about the specification is unclear.
Stock of the long black silicone reinforced coolant cap is live on this page rather than estimated.
Shops order the long black silicone reinforced coolant cap from us in volume because the data on the page is accurate.
If your build is unusual, tell us and we will confirm the long black silicone reinforced coolant cap against it.
The long black silicone reinforced coolant cap ships protected, because a damaged part helps nobody.
Drivers choose the long black silicone reinforced coolant cap here for honest specification detail and quick dispatch.
Details that matter
- Material: Silicone
- Finish: Black
- Category: Universal Hose
- Price: $25.04 with free shipping over $99
- Availability: in stock, dispatched from the USA
Manufacturer specifications
The HPS Performance 9/16″ (14mm) high temperature reinforced black silicone cap is designed specifically to be installed on your cooling system. Vacuum caps have no reinforcement and are intended for vacuum and very little pressure. The HPS reinforced silicone caps are manufactured just like our reinforced silicone radiator hoses. While traditional rubber coolant cap might crack and cause coolant leak, HPS Performance high temperature 3-ply polyester reinforced silicone caps will withstand the high temperatures and pressures of your cooling system for years to come.
HPS Reinforced Silicone Caps are compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
Technical Specification
Product Type: Reinforced Silicone Coolant Cap
HPS Part Number: RSCC-055-BLK
Temperature Range:- 65 deg. F to + 350 deg. F (177 deg. C)
Reinforced Layer: 3-ply Polyester
Inside Diameter: 9/16″ (14mm)
Color: Black
Wall Thickness: 4mm
Inside Length: 1-3/16″
Overall Length: 1-5/8″
UV and ozone resistant
Remark: HPS reinforced silicone caps are not compatible with fuel, oil, or any petroleum-based products.
- Material: 3-Ply Reinforced Polyester Silicone
- Color: Black
- Made of High Temperatureerature 3-ply Polyester Reinforced Silicone. Maximum Temperature Rating: 350 deg. F (177 deg. C).
- Ideal for heavy duty pressure connections and provides excellent resistance for high temperature applications
- Compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
- Inside Diameter: 9/16″ (14mm). Overall Length: 1-5/8″
- HPS reinforced silicone caps are not compatible with fuel, oil, or any petroleum-based products.
Application:
HPS Reinforced Silicone Caps are Universal Fit that compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
Remark:
Installation: Compatible with Water/Coolant ONLY, Not for Fuel/Oil
Product Content:
- 1 x Coolant Cap
The product does not come with manual/instruction, Professional Install Recommended
Cross Reference Number:
- RSCC-150-BLK, RSCC150BLK
Fitment questions get answered by people who work with these parts daily, usually the same business day.
See also: Hoses & Fittings · HPS 3.12″ (80mm) ID, 4″ Leg Long Black 4-Ply Silicone 1/2″ Offset Coupler Hose · HPS 2.25″ (57mm) ID, 6″ Leg Long Black 4-Ply Silicone 1/2″ Offset Coupler Hose · full catalog
Orders are checked against your vehicle details before they are sealed, then dispatched quickly.
Further reading from a neutral source: the fuel economy maintenance guidance.
Questions we get about this part
Will this part fit my vehicle?
Our parts team confirms fitment before the box is sealed. Contact us with your vehicle details and we will settle it in advance.
When will my order dispatch?
We ship from a USA warehouse with quick dispatch, and delivery estimates appear at checkout once you enter your address.
What if it does not fit?
A straightforward returns window applies from delivery. Keep the original packaging until you have test fitted the part and contact support for a fast exchange or refund.
How do you verify this part?
We verify diameter and reinforcement specification on every hose order.
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