Shop-Vac High Performance 90304/90344 Cartridge Filter, Fits most 4-16 Gallon Shop-Vac Wet/Dry Vacuums, High Efficiency HEPA Filter, Washable and Reusable, 1 Pack

Why I reached for this HEPA cartridge

I spend a lot of time in spaces where dust control matters—woodworking one day, drywall patching the next, and the occasional messy clean-up in the garage. After burning through a couple of standard cartridge filters on my 12‑gallon Shop‑Vac, I switched to this HEPA cartridge to see whether it could actually handle the fine stuff without choking my vacuum or spewing haze back into the room. A few weeks of mixed use later, I’m convinced it’s the right upgrade for most Shop‑Vac owners who deal with fine particulates.

Compatibility and fit

This cartridge is sized for most 4–16 gallon Shop‑Vac units. On paper, it’s 7‑9/16 inches in outer diameter and 6‑1/2 inches tall, which matches the common Shop‑Vac cartridge footprint. On my unit, it slid onto the filter cage without fuss and locked down securely with the standard plastic retainer at the base. The seal felt positive—no play, no whistling leaks, and no visible bypass dust on the clean side of the housing after use.

Two practical tips:
- Measure your existing filter or check your model’s manual if you’re unsure. “Most” isn’t “all.”
- Make sure you reinstall the twist‑on bottom retainer. Without it, any cartridge will leak, and you’ll blame the filter when it’s really a missing part.

Filtration performance on fine dust

The key upgrade here is the four‑layer HEPA media. It’s rated to capture at least 99.97% of particles, and while I can’t lab‑verify that claim, the difference in real‑world use is obvious. With drywall sanding, typical cartridges let a faint plume out the exhaust that you can see in a sunbeam; with this HEPA cartridge, that visual haze drops to almost nothing. In the shop, I see fewer dust motes, and surfaces stay cleaner after a cleanup session.

On woodworking debris (sawdust, MDF fines, and router shavings), the cartridge traps the powdery fraction that normally cakes the filter ribs too quickly. I got noticeably longer run time before suction started to taper off. If you pair it with a vacuum bag inside the canister—a step I strongly recommend for drywall and MDF—filter loading slows dramatically, and the vacuum breathes easier for longer.

Airflow and suction

There’s always a trade‑off with denser media: finer filtration can cost you airflow. In practice, the suction on my unit remained strong. Empty can cleanup felt the same as with a standard cartridge, and I only noticed a slight reduction once the pleats were fully dusted from extended sanding. A quick knock‑clean or rinse brought it back. If you’re cleaning big chunks of demolition debris, airflow isn’t the limiting factor anyway; for fine dust, the improved capture is worth the minor resistance.

One small observation: the motor tone smoothed out a bit compared to a clogged standard filter, which I attribute to this cartridge resisting caking better. Less sudden loading means more stable airflow over time.

Wet vs. dry use

The manufacturer rates this cartridge for both wet and dry pickup. It tolerated small amounts of damp debris just fine, and a rinse cleared the pleats quickly. That said, for heavy liquid cleanup (standing water, slurry), I still prefer a foam sleeve and leave the HEPA cartridge for dry or semi‑dry jobs. You can use it wet in a pinch, but:
- Rinse thoroughly after wet use, and
- Let it dry completely (sun or a warm, ventilated spot) before switching back to dry pickup to avoid musty smells and potential mold.

Installation and maintenance

Installation is tool‑free: slide off the old cartridge, clean the filter cage, push on the new one, and twist on the base retainer. Total time: under a minute.

Maintenance is straightforward:
- For light dust: tap the pleats gently against the inside of a trash can to knock off loose debris.
- For heavy fines: rinse from the clean side outward with a low‑pressure stream. Avoid blasting the pleats—high‑pressure water or compressed air can tear HEPA media.
- Dry fully before reinstallation. I set it in the sun or near a fan until there’s zero dampness between the pleats.

Washability is the selling point. I cycled mine through three rinse/dry rounds over a few weeks with no delamination, warping, or end‑cap looseness. As with any cartridge, the pleat edges will eventually show wear, but the service life here feels meaningfully longer than a basic paper cartridge.

Build quality

The pleats are uniform and tightly spaced, with clean bonding at the end caps. The core feels rigid enough to resist collapse under suction, and the outer mesh guards the media from accidental nicks. I didn’t see glue drips, cracked caps, or misaligned pleats—issues that do pop up with bargain filters. It looks and feels like a proper HEPA‑grade cartridge rather than a relabeled standard filter.

Real‑world results

A few scenarios where this cartridge stood out:
- Drywall dust: Noticeably less airborne haze and less smell of “dusty air” after cleanup. Surfaces stayed clean longer, and the vacuum’s exhaust didn’t redistribute fines across the room.
- MDF and sanding fines: The pleats loaded more slowly, and suction stayed consistent through longer sessions.
- Garage cleanup: Typical dirt, leaves, and general debris posed no issues. The cartridge didn’t clog prematurely with mixed debris, which sometimes happens with ultra‑fine media.

I also liked that the filter didn’t leak around the base or lid—an all‑too‑common failure point on cheaper cartridges. The seal integrity is critical; even a “HEPA” label won’t help if air bypasses the media. Here, the fit and retainer do their job.

Value

Compared to OEM HEPA cartridges, this one is competitively priced and, in my experience, delivers equal or better performance on fine dust. The ability to rinse and reuse extends the life, especially if you use a bag or a cyclone pre‑separator to keep the heavy material off the pleats. Over a few months of mixed use, I’d expect it to pay for itself versus buying multiple standard cartridges.

What could be better

No cartridge is perfect. A couple of notes:
- HEPA claims in the shop‑vac world are rarely third‑party certified. Performance is excellent, but if you need certified HEPA for regulated work, verify documentation with your job requirements.
- While it can handle wet pickup, a foam sleeve is still a better match for large volumes of liquid. Consider this HEPA cartridge primarily a dry‑use workhorse.

Who it’s for

• Home remodelers managing drywall dust and fine plaster
• Woodworkers dealing with MDF, routing, sanding, and general shop dust
• Pet owners and garage users who want cleaner exhaust air during routine cleanup
• Anyone who wants fewer filter changes without sacrificing suction

If your work is mostly heavy debris or wet messes, a standard cartridge plus a foam sleeve may be more cost‑effective. If fine particulate is the problem, this HEPA cartridge is the clear step up.

Practical setup tips

• Use a high‑quality bag inside the canister for drywall, MDF, and ash. The bag captures the bulk; the HEPA cartridge polishes the air.
• Check the filter cage gasket and lid seal. A great filter can’t compensate for leaky housings.
• Mark your rinse dates with a Sharpie on the end cap. It’s an easy way to track maintenance and diagnose performance changes.
• Replace on condition, not just a calendar date. If rinsing no longer restores airflow or the pleats look frayed, it’s time.

Recommendation

I recommend this HEPA cartridge for most Shop‑Vac owners who care about fine dust capture and want a reusable filter that doesn’t kneecap suction. It fits securely, filters noticeably better than standard cartridges, cleans up well with a rinse, and holds up to repeated use. Pair it with a bag for best results, keep it dry between sessions, and it will make your vacuum feel more capable—especially on the jobs that generate the most airborne dust.