KISYONGUS 2 Pack Vacuum Breaker Repair Kit Replacement for VACVBKX1B, Outdoor Faucet Repair Kit, ASSE 1019-A Vacuum Breaker for Traditional Anti Siphon Frost Free Sillcock Valves Anti Siphon Valve Repair Kit

Why I reached for this kit

A leaky vacuum breaker at a hose bib is one of those small annoyances that wastes water and can undermine the backflow protection you actually want on a frost‑free spigot. I keep a few repair kits on hand for quick fixes, so I tried the Kisyongus vacuum breaker repair kit on two frost‑free, anti‑siphon sillcocks at my place to see if it could be a straightforward, tool‑free solution.

This kit is a two‑pack of yellow vacuum breaker assemblies marketed as compatible with ASSE 1019‑A frost‑free valves and positioned as a replacement for the VACVBKX1B pattern. The value proposition is clear: screw out the old, screw in the new, restore anti‑siphon function and stop the drip—all without tools. That’s exactly what I wanted.

Design and build

Each unit arrives neatly packaged and visually well made. The molding on the yellow cap and body is clean with no flashing, the threads feel crisp, and the internal moving parts operate smoothly. The O‑rings are properly sized and pliable, not the plasticky kind that crack the moment you stretch them. Overall, it looks and feels like a decent OE‑style assembly rather than a flimsy universal.

There are no exotic materials advertised here—this is very much a standard vacuum breaker assembly for a frost‑free hose bib with a vented cap, a central plunger, spring, and sealing O‑rings. That’s the architecture you want: simple, serviceable, and easy to diagnose if something goes wrong later. The bright yellow color makes it easy to spot and identify at a glance, which I appreciated during installation and testing.

Installation experience

The promise is tool‑free installation, and in many cases that’s how these should go. You remove the hose, back out the old vacuum breaker cap/assembly by hand, check that the sealing surface is clean, and thread in the new unit until it seats. A little silicone plumber’s grease on the O‑rings is always a good idea to prevent tearing and help the assembly seat smoothly.

Here’s where my experience diverged by fixture:

• On my newer frost‑free sillcock, the Kisyongus assembly would not start in the threads. The male thread on the kit was larger than the female threads on my hydrant’s breaker pocket. I stopped before forcing anything; cross‑threading is a good way to buy yourself a new hydrant.
• On my older wall hydrant, the story was the same—the kit’s threads were just a touch too large to bite. No amount of gentle persuasion would get it to start.

In both cases, the leak I was addressing was minor weeping at the vacuum breaker cap during flow. Since the kit’s O‑rings were a match for the ones in my existing assemblies, I transplanted the O‑rings into my original caps, lubricated them, reassembled, and the leaks stopped immediately. So while I couldn’t install the entire Kisyongus assembly on either of my fixtures, the included seals were directly useful and solved my immediate problem.

I want to underscore that vacuum breaker assemblies for ASSE 1019‑A wall hydrants are not universal. The ASSE standard defines performance, not a single thread or geometry. Many manufacturers use different diameters and thread forms for the breaker pocket, and even a small difference will prevent a new cap from threading. That’s not a knock on this kit specifically—it’s a reality of the category.

Performance and anti‑siphon function

On a correctly matched hydrant, a replacement vacuum breaker should do three things well:
- Seal under pressure so water doesn’t weep from the cap.
- Open its air vent when the faucet is shut to break any vacuum and prevent back‑siphonage.
- Survive seasonal use outdoors without binding up.

I did verify the performance of the O‑rings from this kit on my existing caps: no more weeping under full house pressure and a proper gulp of air when the faucet is shut, which is what you want to see and hear. The spring and plunger action in the Kisyongus assemblies I handled felt smooth and appropriately sprung, so I don’t have concerns about the mechanism itself. The caveat is simple: you need to be sure the whole assembly actually fits your hydrant.

Compatibility: the make‑or‑break detail

The packaging and listing call out compatibility with ASSE 1019‑A and replacement for VACVBKX1B. In practice, here’s how I recommend checking before you buy:

• Identify your hydrant. Look for a brand and model tag or stamping on the wall plate, handle, or body of the spigot. Many manufacturers publish exploded parts diagrams that list their specific vacuum breaker kit by number.
• Measure the existing cap. If you have calipers, measure the outside diameter of the male thread on your old cap, and compare it to the replacement you’re considering. Even a couple of millimeters’ difference will be a no‑go.
• Inspect the thread form. Some hydrants use fine, shallow threads; others use coarser profiles. Visual comparison helps if you have the part in hand.
• Bring the old cap if buying locally. Matching by eye with the physical part avoids returns.
• Don’t assume ASSE 1019‑A means “universal fit.” It doesn’t.

If your hydrant explicitly calls for a VACVBKX1B‑style replacement, this Kisyongus kit should be a good match. If you’re guessing based on the standard alone, you’re rolling the dice.

What I liked

• Two‑pack value: Having a spare on hand is practical. Outdoor fixtures seem to pick the least convenient moment to start dripping.
• Clean molding and smooth action: The assemblies feel like quality replacements, not generic throwaways.
• O‑ring usefulness: Even without a perfect thread match, the seals solved my leak on two hydrants. Keeping a pair of fresh O‑rings in the shop is never a bad idea.
• Tool‑free concept: When it fits, this is a five‑minute fix with no need to shut off water to the house.

What could be better

• Clearer sizing information: A simple dimensional diagram (major thread diameter, pitch, cap height) would save a lot of guesswork and returns.
• Broader compatibility guidance: A cross‑reference list of popular hydrant brands/models that use the VACVBKX1B style would help homeowners quickly confirm fit.
• Labeling by size family: Color‑coding or a visible size code on the packaging would make it easier to distinguish among similar kits.

Who it’s for

• Homeowners and maintenance staff who know their hydrant model or have confirmed a VACVBKX1B‑style breaker.
• Anyone comfortable swapping out small plumbing assemblies on outdoor fixtures.
• People troubleshooting minor weeping from the top of a frost‑free hydrant and looking for a quick, tool‑free fix.

Tips for a smooth install

• Shut off the water to the spigot if your hydrant doesn’t isolate cleanly.
• Clean the breaker pocket threads with a soft brush before installing the new cap.
• Lightly lubricate the O‑rings with silicone plumber’s grease.
• Hand‑tighten only. The cap needs to vent; don’t over‑torque or use thread sealant.
• Test with a hose attached and under full pressure, then shut the valve and listen for the vent to admit air.

The bottom line

The Kisyongus vacuum breaker repair kit is a well‑made, budget‑friendly replacement that delivers exactly what it promises—provided your hydrant matches the VACVBKX1B pattern. In my case, the assemblies didn’t thread into either of my frost‑free sillcocks, which highlights the biggest challenge in this category: fitment varies more than most people expect. Even so, the included O‑rings were worth the price of admission by themselves; they cured small leaks and restored proper function on my existing caps.

Recommendation: Conditional. I recommend this kit if you’ve verified compatibility with your specific hydrant (ideally by model number or by matching the old cap). If you cannot confirm fit, I’d steer you to a local plumbing supply where you can compare parts in person, or to a replacement kit explicitly listed for your hydrant’s brand and model. When it fits, this is an easy win; when it doesn’t, it’s still a handy source of seals—but that’s not the best way to buy a repair kit.