ECKJ 210PCS 304 Stainless Steel Hex Nuts Assortment Kit for Screw Bolt with 6 Sizes DIN 934 (M3 M4 M5 M6 M8 M10) Great Replacement Fasteners for Professionals, Repairmen or DIY, Meet Your Every Needs

A compact, capable metric nut kit that earns its spot in the drawer

I picked up the ECKJ hex nut kit after yet another weekend project stalled over a missing M6 nut. Rather than making a hardware store run for a single fastener, I wanted a compact, metric-focused assortment I could keep within reach. After a few weeks of use across small repairs and shop tasks, this 210-piece set has proven to be the kind of “why didn’t I get this sooner?” standby that quietly solves problems.

What you actually get

This is a straightforward assortment of standard hex nuts in six metric sizes: M3, M4, M5, M6, M8, and M10. Threads are the common coarse pitches—M3-0.5, M4-0.7, M5-0.8, M6-1.0, M8-1.25, and M10-1.5—which matches the majority of bolts and machine screws in household, hobby, and general maintenance use. The nuts conform to DIN 934 dimensions, which helps with compatibility and wrench sizing.

Material is 304 stainless steel (the general-purpose “A2” stainless). That brings strong corrosion resistance for indoor/outdoor projects and damp environments, without the brittleness or staining you can see with cheaper zinc-coated kits. They come in a small plastic organizer (about 4.33 x 2.83 x 0.77 inches) with individual compartments for each size—pocketable, easy to toss in a toolbox, and unobtrusive on the bench.

Worth noting: these are standard hex nuts, not nyloc or prevailing torque lock nuts. If you need vibration resistance without a separate washer, this kit isn’t that. Think of it as the basic, dependable core set you’ll use with bolts, threaded rod, or machine screws.

Fit and finish

Out of the box, the nuts have a consistent stainless finish, clean flats, and minimal burrs. Thread engagement with matching bolts has been smooth across the range. I checked a sample of each size with thread gauges and calipers; dimensions were where I expected them for DIN 934 hardware. Across several projects—mounting a router plate, assembling a workbench jig with M6 hardware, and fixing a leaky faucet handle—the fit was uneventful in the best way. Wrench flats didn’t round off, and threads mated cleanly.

I did encounter a couple of M3s with imperfect threads that didn’t want to start easily on a screw. That’s not unusual in large assortments, and the failure rate was low enough that it didn’t affect the overall usefulness. If you rely heavily on the smallest sizes, it’s worth keeping a thread chaser on hand or simply weeding out the occasional dud.

In use: where it shines

• Household and appliance fixes: Metric is increasingly common on newer appliances and fixtures. The M4–M6 range covered everything I’ve touched lately, from a door lockset trim screw to a faucet handle.
• Hobby and light mechanical: RC builds, 3D printers, camera rigs, and small robotics often use M3/M4/M5. Having those sizes ready saved me more time than I care to admit.
• Shop and jig work: For temporary jigs and fixtures on the bench, being able to pair a bolt from my stash with a matching nut on the spot is exactly why kits like this exist.
• Outdoor use: 304 stainless resists rust well in typical outdoor exposure. For coastal, marine, or chemical environments, 316 stainless is the safer choice—this kit is solid for garden fixtures and patio hardware, but I’d step up to 316 where salt spray is a factor.

The strength is appropriate for general fastening. If you’re working on critical automotive suspensions or high-stress applications, you’ll likely want graded hardware matched to the application. For everything else, these are exactly the kind of nuts you reach for without overthinking it.

Organization and portability

The organizer is compact and keeps sizes separated. I labeled the lid with a marker for quick identification, which sped up selection. The case is fine for a drawer or tool bag, but it’s not jobsite-tough. If you tend to drop kits off ladders or toss them around in a truck box, consider decanting into a sturdier organizer. For most shop users, the included case is adequate.

One practical tip: the smallest sizes (M3/M4) are fiddly by nature. A magnetic parts tray and a pair of tweezers or needle-nose pliers will save your patience when fishing them out.

Stainless realities: anti-seize and galling

Stainless-on-stainless can gall under pressure, especially if you drive fasteners quickly without lubrication. It’s not a defect of this kit; it’s the nature of 304 stainless. A tiny dab of anti-seize or a light machine oil on threads prevents binding and makes removal a non-event later. I used nickel anti-seize on M6/M8 assemblies and had zero issues.

Coverage and gaps

This assortment covers a smart spread of everyday metric sizes, but a few limitations are worth mentioning:

• Metric only: If your projects are mostly SAE/imperial, you’ll want a different kit or a parallel SAE set.
• Coarse pitch only: These are standard coarse threads. If you need M10x1.25 fine, for example, this isn’t that.
• No washers or lock hardware: It’s nuts only—no flat washers, spring washers, or nylocs. Keep a separate kit if you need vibration resistance.
• Size distribution: Assortments typically include more of the middle sizes (M4–M6) than the largest; that matches how I use them, but heavier users of M8/M10 may run short sooner.

None of these are deal-breakers; they just define what the kit is designed to be: a good, general-purpose metric nut set.

Quality and consistency

On balance, the quality is solid for the price-per-piece category. Threads are cut cleanly with consistent pitch; the nuts seat squarely; wrench flats are true. Across roughly a couple dozen fastenings, I only culled a couple of small nuts that didn’t meet my expectations. Dimensional consistency paired well with bolts from multiple brands, including stainless, zinc-plated, and black-oxide machine screws.

If you’re assembling critical mechanisms where tight tolerance is mandatory, you’ll likely be buying hardware by specification anyway. For repair, maintenance, and workshop work, the consistency here is entirely satisfactory.

Practical advice for best results

• Verify metric vs SAE: If you’re replacing a missing nut, confirm the bolt is metric. An M6 and a 1/4-20 look similar but won’t mate correctly.
• Use anti-seize with stainless: Especially on larger sizes and higher torque.
• Add a washer assortment: It expands what this kit can do and protects surfaces.
• Label the case: Quick size ID speeds up selection, particularly for M3–M5.
• Don’t overtorque: 304 stainless is tough but not indestructible; use appropriate torque for the bolt diameter and material.

Who it’s for

• DIYers and landlords who tackle periodic repairs and want a ready answer to “where’s a matching nut?”
• Hobbyists working with metric-heavy gear like 3D printers, drones, RC vehicles, and camera rigs.
• Tinkerers and shop users who prefer a tidy, compact kit rather than rummaging through coffee cans of mixed hardware.

If your work is heavily automotive, marine, or industrial, you may want kits focused on 316 stainless, nyloc selections, or graded lock hardware to match your use cases.

The bottom line

The ECKJ hex nut kit does exactly what a good hardware assortment should: it removes friction from small repairs by making the most common metric sizes easy to grab, consistent to use, and resistant to rust. The 304 stainless construction, DIN 934 conformity, and compact organization make it a reliable, low-maintenance addition to a home shop or tool bag. It’s not a lock-nut set, not a fine-thread assortment, and not designed for heavy industrial abuse—but it doesn’t claim to be.

Recommendation: I recommend this kit as a practical, good-value metric nut assortment for general repairs, maintenance, and hobby work. It covers the sizes you’re most likely to need, the stainless material holds up in real-world conditions, and the compact case keeps the chaos under control. Add a washer set and a dab of anti-seize, and you’ll be prepared for the vast majority of “missing nut” moments that derail small projects.