Replace this with a real customer quote — how the brass cap held a seal where the plastic OEM cap was the slow leak, and how it threads onto the service valve without galling.
Service Cap
HCBC1/4Solid brass service-port cap with valve depressor — the secondary seal your 1/4" SAE ports actually need
A2L SafeSolid Brass1/4" SAECaptive Gasket
$14.96
Out of stock· backorder available
Direct from the manufacturer — Miami HQ, full warranty & tech support included.
Out of stock
Designed
In Miami, USA
Warranty
1-Year Full
Ships
1–2 Days
- Field-tested by working HVAC technicians
- Free returns within 30 days
- Direct manufacturer support — Miami HQ
- ORDER IN THE NEXT — AND IT SHIPS TODAY FROM MIAMI
2ndSEAL
Required Secondary Seal
The brass service cap is the system's secondary seal — not optional. The #1 source of slow leaks is an uncapped or cracked-plastic service port
SOLIDBRASS
Solid Brass Body
Forged brass goes on hand-tight and won't crack, strip, or UV-rot like the throwaway plastic caps that ship on new equipment
1/4"SAE
Universal 1/4" Fit
Threads onto any standard 1/4" SAE service port — split systems, mini-splits, line-set valves, and gauge ports
HCPRODESIGNED
Built to Black Knight Spec
HCPRO-designed to Black Knight specifications and quality-control standards — engineered in Miami, built to spec by our manufacturing partner
Why Black Knight
The secondary seal.
Solid brass.
Fits every 1/4" port.
The HCPRO Black Knight brass service cap is the secondary seal your service ports actually need — solid brass with a captive gasket and built-in valve depressor, in place of the cracked plastic cap that's leaking right now.
The seal techs forget — until it leaks
The Schrader core isn't the system's only seal — the service-port cap is the secondary seal, and on most slow-leak callbacks it's the part that failed: missing, finger-loose, or a cracked plastic OEM cap. This solid brass cap carries an internal sealing gasket that pulls bubble-tight by hand, so the port that techs ignore stops being the leak you get called back for.
Solid brass with a captive gasket
Forged brass body with a captive sealing gasket and a built-in valve depressor for positive core contact. Brass threads won't gall or strip on aluminum service valves, and the cap won't crack in the sun or split when you torque it — the way the bagged plastic caps do their second summer.
Fits every 1/4" SAE port
Standard 1/4" SAE threads fit split systems, mini-splits, line-set service valves, and gauge ports across every common refrigerant — R-410A, R-22, R-134a, R-404A, R-1234YF, R-32, R-454B. Keep a handful in the service bag and re-cap every port you touch, properly, with brass.
Full Product Description
Pack of 6 solid-brass 1/4" SAE service-port caps with captive sealing gaskets and built-in valve depressors — enough to re-cap a whole system and keep spares in the truck. The secondary seal that stops the slow leaks cracked plastic OEM caps cause.
Key features
- Set of 6 — one per service port, plus spares for the truck
- Solid forged brass won't crack, strip or UV-rot like plastic OEM caps
- Captive internal gasket pulls bubble-tight by hand for a positive secondary seal
- Built-in valve depressor for positive Schrader-core contact
- Fits any 1/4" SAE service port — split systems, mini-splits, line-set and gauge ports
- HCPRO-designed to Black Knight specifications
Re-cap every service port you touch with brass — six to a pack, so you're never short on the job.
Technical specifications
Brass cap specs for a leak-tight service port.
HCPRO Black Knight brass service cap — solid brass, captive gasket, built-in valve depressor. The secondary seal for 1/4" SAE service ports, in place of the cracked plastic cap that ships on new equipment. HCPRO-designed to Black Knight specifications.
Type
Brass service-port sealing capSecondary seal for 1/4" SAE service ports — with built-in valve depressor
Body
Solid forged brassWon't crack, strip, or UV-rot like plastic OEM caps
Internal seal
Captive sealing gasketPulls bubble-tight by hand for a positive secondary seal
Fits
1/4" SAE service portSplit systems, mini-splits, line-set valves, gauge ports
Function
Secondary seal / leak protectionBacks up the Schrader core — the #1 missed slow-leak source
Compatible refrigerants
R-410A, R-22, R-134a, R-404A, R-1234YF, R-32, R-454BAll common HFC, HFO, and A2L refrigerants
Grip
Hand-tight hexSeats by hand; snug with a wrench — no tools required to seal
Brand
HCPRO Black KnightThe HCPRO professional HVAC service tool line
Country of origin
ChinaHCPRO-designed in Miami to Black Knight specifications, built to spec and quality-controlled to OEM standards
Connection standard
SAEStandard SAE threads fit all professional HVAC service ports
Warranty
1-year limitedCovers manufacturing defects under normal professional use
In the box
The cap, ready to seal the port for good.
HCPRO Black Knight brass service capSolid forged brass, 1/4" SAE — the secondary seal your service port needs
Captive sealing gasketPre-installed inside the cap for a bubble-tight positive seal — pairs with HCPRO replacement gaskets
Built-in valve depressorIntegrated pin for positive Schrader-core contact
Customer reviews
What working techs say after putting it on the truck.
12,000+
HVAC pros served
4.9★
Average rating
94%
Repeat buyers
Replace this with a real customer quote — how the brass cap held a seal where the plastic OEM cap was the slow leak, and how it threads onto the service valve without galling.
Replace this with a real customer quote — how the brass cap held a seal where the plastic OEM cap was the slow leak, and how it threads onto the service valve without galling.
Common questions
Answers from the warehouse floor.
Still stuck? Call our techs at 305-720-0044.
Does HCPRO warranty the products?
Yes — every HCPRO Black Knight product ships with a 1-year limited warranty against manufacturing defects under normal professional use. See our full warranty terms.
Why does a service-port cap matter?
The Schrader core is the primary seal, but it's a small spring-loaded valve — it weeps. The brass cap is the secondary seal, and on most slow-leak callbacks it's the part that failed: missing, hand-loose, or a cracked plastic OEM cap. A solid brass cap with an internal gasket stops the leak the core can't.
What does it fit?
Any standard 1/4" SAE service port — split-system service valves, mini-splits, line-set valves, and gauge/manifold ports. It works on every common refrigerant, including R-410A and A2L systems like R-32 and R-454B.
Why brass instead of the plastic cap it came with?
The plastic caps that ship on new equipment crack in UV, strip easily, and split when torqued — which is exactly why they're a leak source by their second summer. Solid brass won't crack or rot, threads cleanly onto aluminum service valves without galling, and carries a captive gasket for a positive seal.
What is the valve depressor for?
The cap has an integrated depressor for positive contact against the Schrader core, ensuring the cap seats squarely and seals the port. Tighten it hand-snug; a quarter turn with a wrench locks the gasket bubble-tight.
Can I replace the internal gasket?
Yes — the cap uses a standard sealing gasket. If it ever wears, HCPRO sells replacement neoprene gaskets so you can re-seal the cap instead of replacing it. Keep a few in the bag.
Do you offer bulk pricing?
Yes — trade pricing on this page, plus volume discounts for shops. Email hcproproductsusa@gmail.com with your quantities for a custom quote within 24 hours.
Can I return an unused cap?
Yes — free returns within 30 days for unused items in original packaging. Read our full return policy.
If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, within 24 hours on weekdays.
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Shipping Information
- FREE SHIPPING for full pallet orders going to zoned industrial addresses within the freight delivery network that have a 48-inch loading dock and access for 53-foot trailers. If you are not sure if your location qualifies for free shipping, please CONTACT US HERE.
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Customer Support
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FAQ’s
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