Mr. Pen - Bolts, Nuts, and Washer Assortment Kit, 113 pcs, Assorted Nuts and Bolts, Washer Kit

Why I Keep This Kit Within Arm’s Reach

I didn’t expect a small, clear box of fasteners to streamline my day-to-day tinkering as much as this one has. The Mr. Pen kit is exactly what it claims to be: a compact, metric assortment of bolts, nuts, and washers that covers a lot of everyday fixes without forcing me to run to the hardware store. It’s not a contractor’s bulk bin, and it’s not intended for structural work, but for household repairs, hobby builds, small machinery, and electronics enclosures, it’s become a quiet, reliable helper on my bench.

What’s in the Box

You get 113 pieces, organized into:
- 36 bolts in six small metric sizes
- 39 nuts across three matching sizes
- 38 washers across three matching sizes

Everything arrives pre-sorted in a clear, compartmentalized organizer. The assortment focuses on the small end of the metric range—the sizes I reach for when replacing a missing fastener on a small appliance, securing a panel on a printer or router, or mounting brackets on furniture and fixtures.

The assortment is balanced: you have enough nuts and washers to pair with the bolts, and the distribution tends to match how I actually use fasteners (washers and nuts go faster than bolts in certain builds). It’s not exhaustive, but it’s thoughtfully curated for general-purpose tasks.

Materials and Finish

All the pieces are galvanized for corrosion resistance. This matters more than you might think for indoor projects—garages and basements can be humid, and untreated hardware develops surface rust quickly. The galvanization on my kit is uniform, with no obvious drips or heavy buildup on the threads. Threads start by hand cleanly, and I haven’t encountered any burrs that required chasing with a die.

It’s important to set expectations here: this is not stainless steel, and it’s not graded for high-stress applications. For most household projects, the galvanized finish offers a good balance of durability and rust resistance. If you’re building fixtures for marine environments or constantly dealing with spray or outdoor exposure, stainless is still the better choice. For everything else, these hold up fine.

Organizer and Usability

The clear organizer is more than an afterthought. Being able to see contents at a glance makes it easy to grab what I need without dumping parts on the bench. The compartments fit the assortment well, and the layout is simple enough that I rarely mis-sort pieces when I’m done.

A couple of notes:
- The dividers are mostly fixed. If you’re planning to combine this with other assortments or custom sizes later, space is limited.
- The latches are serviceable, but it’s still a light-duty case. I wouldn’t toss it loosely in a tool bag full of heavy steel. On a shelf or bench, it’s perfectly adequate.

One practical tip: drop a small label in each compartment with the size once you’ve confirmed the threads. It speeds up repeat tasks and prevents mixing sizes when you’re working quickly.

Real-World Use

I’ve used the kit for:
- Reattaching a metal shroud on a small shop fan where the original bolt went missing
- Mounting standoffs in a 3D printer enclosure
- Securing a replacement hinge on a toy chest
- Replacing hardware on a lamp base and an electronics project box

In each case, the threads mated consistently, and the washers laid flat without cupping. I’ve torqued these down with a nut driver and a small wrench set without any stripping or flaking of the galvanization. The sizes available in the kit cover the most common small-machine needs, and I haven’t had to compromise with “close enough” fits. Washers are a good match to the bolt diameters, and they distribute load well on softer materials like plastic and wood.

Performance and Tolerances

For a general-purpose assortment, thread quality is more than acceptable. Threads engage smoothly, even on slightly painted or powder-coated surfaces, and fasteners seat square without wobble. I inspected a handful under magnification and found clean cut threads and uniform plating. A couple of washers had light stamping marks on the edges, which I could knock down with a quick pass on a file if needed, but they function fine as-is.

Torque-wise, this hardware is ideal for light-to-medium duty applications. It’s not meant for automotive or load-bearing structures. If you need high-grade bolts (e.g., graded metric fasteners for engine mounts or suspension components), look elsewhere. For cabinetry, light fixtures, guards, covers, brackets, and panel assemblies, the kit is right in the pocket.

Limitations

Every assortment has tradeoffs. Here’s what stood out:
- Metric only: Great for most electronics and many imported appliances and fixtures, but it won’t help with imperial-thread replacements. If you work in mixed environments, you’ll want a companion imperial kit.
- Range breadth: Six bolt sizes and three nut/washer sizes cover a lot, but not everything. If your work often requires very long or very short fasteners, or specialized heads, this kit alone won’t cover you.
- Organizer durability: Fine for shelves and drawers, less so for abuse in a mobile toolbox. If you plan to travel with it frequently, consider transferring the contents to a sturdier case.

These aren’t dealbreakers, but they’re worth knowing so you can set up your workspace accordingly.

Value and What It Replaces

I used to buy fasteners piecemeal at the hardware store, which is not cost-effective for small projects and leads to a graveyard of half-used plastic bags. This kit gets me out of that habit. The per-piece cost is significantly lower, and I’m no longer cobbling together near matches from whatever’s left over.

For most home shops, a single kit like this covers routine needs. If you’re a pro or a serious hobbyist, you’ll eventually round it out with a second kit (imperial), a few dedicated sizes you burn through, and head styles you prefer for specific jobs. But as a core, ready-to-go assortment, this hits the mark.

Who It’s For

• DIYers who frequently assemble furniture, repair appliances, or build small projects
• Makers and electronics hobbyists who need common metric machine sizes on hand
• Light-duty maintenance in shops where metric is common
• Anyone tired of hunting for a single bolt mid-project

If your work leans heavily toward automotive, marine, or outdoor structural builds, skip general assortments and buy graded or stainless hardware in targeted sizes instead.

Tips to Get the Most from the Kit

• Add a pocket-size metric thread gauge and a set of nut drivers or a small socket set. You’ll identify sizes faster and avoid cross-threading.
• Label compartments with sizes once verified. If you add refills later, your system will still make sense in six months.
• Use washers on soft materials to spread load and keep finishes intact.
• Don’t over-torque galvanized hardware; snug plus a quarter turn is enough for most light assemblies. If you need higher clamp load, step up to graded fasteners.

Final Take

The Mr. Pen kit delivers exactly what I want from a general-purpose metric assortment: consistent, rust-resistant hardware in the small sizes I reach for most, packed in an organizer that keeps me moving. The thread quality is reliable, the coating holds up, and the selection is practical for everyday repairs and builds. It won’t replace specialized, graded, or stainless stock, and the case is best treated with a bit of care. But as a staple on the bench, it’s hard to argue with.

Recommendation: I recommend this kit for anyone who wants a compact, dependable set of small metric bolts, nuts, and washers on hand for routine repairs and hobby projects. It saves time, reduces trips to the store, and covers the most common needs without fuss. If you require heavy-duty, marine, or imperial hardware, pair it with targeted additions—but for general shop use, this is a smart, cost-effective foundation.