The best M6 stainless steel screws depend on whether you need a specific screw length or a ready-to-use assortment. For mixed repairs, the Hapric kit offers eight sizes and installation tools, while the 170-piece kit provides several lengths with nuts and washers. Mr. Pen covers seven lengths, and the Mellewell screws are single-length Phillips-drive options for buyers who know the exact size they need.
| Product | Best For | Notable Details |
|---|---|---|
| Hapric 172-Piece Kit | General repairs and projects | Eight sizes, washers, hex key, and tweezers |
| 170-Piece M6 Kit | Metric fastener assortment | Seven listed lengths, nuts, and washers |
| Mr. Pen 146-Piece Kit | Multiple lengths up to 35 mm | Seven screw lengths and assorted hardware |
| Mellewell 20 mm Screws | Exact 20 mm replacement | Phillips drive, full thread |
| Mellewell 16 mm Screws | Exact 16 mm replacement | Phillips drive, full thread |
Hapric 172-Piece M6 Screw Assortment
Best for: Buyers who want a varied M6 kit for repairs, furniture installation, or 3D printer projects. It includes 304 stainless steel screws in eight metric sizes, plus nuts, flat washers, lock washers, a hex key, tweezers, and a storage box.
The maker lists 172 pieces: 48 screws, 24 nuts, 50 flat washers, and 50 lock washers. The included tools are useful when handling small hardware or tightening hex socket screws. The assortment is selected for its combination of fasteners and accessories rather than for a large quantity of any one screw length.
Limitation: The kit contains multiple lengths, so check the included size breakdown before relying on it for a project that needs a specific quantity of one length.
170-Piece M6 Hex Socket Screw Kit
Best for: Buyers who need a broad assortment of M6 hex socket head cap screws with matching hardware. The kit includes 304 stainless steel screws in seven listed lengths: 8, 10, 12, 16, 20, 25, and 30 mm. It also includes 32 hex nuts, 46 lock washers, and 46 flat washers.
The recessed Allen-style drive is designed for tightening with a hex tool, and the listing describes burr-free threads. This kit is a practical choice for routine installation and repair when several screw lengths may be needed. Its stainless steel construction is specified as 304.
Limitation: The listed screw counts vary by length, and the longest listed screw is 30 mm. Check the count for each size if your job requires several matching fasteners.
Mr. Pen 146-Piece M6 Assortment
Best for: Buyers looking for M6 button head socket cap screws in seven lengths. The listed sizes are 10, 12, 16, 20, 25, 30, and 35 mm. The 146-piece assortment also includes nuts, flat washers, and lock washers.
The kit is described as stainless steel and is suited to projects where keeping multiple lengths of metric hardware together is useful. Choose it if you need a range that includes 35 mm screws and prefer an assortment over buying each length separately.
Limitation: The listing does not specify a stainless steel grade or provide the quantity of each individual screw size in the supplied product details. Confirm those details if material grade or exact counts matter.
Mellewell M6 20 mm Truss Head Screws
Best for: Buyers who need a specific 20 mm M6 machine screw rather than a selection of lengths. This pack contains 25 full-thread truss head screws made from 18-8 stainless steel, identified in the product details as stainless steel 304.
The screws have a 6 mm thread diameter, 1 mm thread pitch, and Phillips drive. Choose this pack when those measurements and the truss head style match the existing hardware or project requirements.
Limitation: This is a single-length pack, not an assortment. It uses a Phillips drive, so it is not the right choice when a hex socket drive is required.
Mellewell M6 16 mm Truss Head Screws
Best for: Buyers replacing or sourcing 16 mm M6 screws in a defined style. The pack includes 25 full-thread truss head machine screws made from 18-8 stainless steel, with the product details identifying the material as 304 stainless steel.
Each screw has a 6 mm thread diameter and 1 mm pitch, with a Phillips drive. This fixed-size option is easier to match to a known specification than a mixed kit when the required length is 16 mm.
Limitation: The pack does not provide alternative lengths or drive styles. Verify the head style and length against your application before ordering.
Buying Guide: How To Choose M6 Stainless Steel Screws
Do you need an assortment or a specific length?
Choose an assortment if you handle varied repairs and are unsure which lengths a project may require. Compare the included size range and the number of screws per size. For a known replacement, a single-length pack such as the 16 mm or 20 mm Mellewell option avoids extra sizes you may not use.
What does M6 mean, and what measurements should you check?
M6 identifies a metric thread with a nominal 6 mm diameter. Thread diameter alone is not enough to confirm a match. Check the screw length, thread pitch, head shape, and drive type. The Mellewell products specify a 1 mm pitch; do not assume every screw style or application uses the same specification without checking.
Which head and drive style fits your project?
Hex socket screws use a hex tool and can suit projects where that drive is required. Truss head screws have a different head profile, and the Mellewell packs use a Phillips drive. Match the replacement to the existing fastener or the project’s design rather than choosing by length alone.
When do nuts and washers matter?
Assortment kits with nuts and flat or lock washers can be useful when the joint calls for those parts. A washer may help spread the load, while the kit listings describe lock washers as components intended to help resist loosening. Confirm that the fastener arrangement suits the materials and application.
Is stainless steel grade important?
Some options identify the material as 304 or 18-8 stainless steel, while the Mr. Pen listing only says stainless steel. If a particular grade is important for your project, select a product with that grade explicitly stated and confirm the requirements for the environment where it will be used.
Frequently Asked Questions
Are all M6 screws the same length?
No. M6 refers to the nominal thread diameter, not screw length. These products include lengths from 8 mm to 35 mm, depending on the kit or pack.
What is the thread pitch of the Mellewell screws?
The listed pitch is 1 mm for both the 16 mm and 20 mm Mellewell screws.
Which option includes the widest listed length range?
The Hapric kit lists lengths from 8 to 35 mm. Mr. Pen lists seven lengths from 10 to 35 mm.
Do the Mellewell packs include nuts and washers?
The supplied product details describe packs of 25 screws and do not list nuts or washers. Choose an assortment if you need those additional parts included.