Hex Head Bolts M6 x 40mm

Key specifications

The black coating is the standout detail here: it gives these full-thread hex bolts a dark finish, while the listed material is 18-8 stainless steel (304). That combination may suit projects where you want stainless hardware without a bright metal appearance. The pack contains M6 x 40mm bolts, so matching the size to the parts being joined matters more than the broad application list suggests.

Each bolt has a 6mm thread diameter, a 1.0mm thread pitch, and a 40mm length. The head measures 12mm across and 8mm high. A wrench is listed for installation, no special tools are specified. The description does not give a load rating or installation torque, so these measurements alone are not enough to assess whether a bolt is suitable for a structural or otherwise demanding application.

Who it’s for

These are aimed at people assembling furniture, working on woodworking projects, or handling repairs involving home or office appliances, communications equipment, or machinery. They make most sense when you already know you need an M6 x 40mm, full-thread bolt and want a hex head that can be tightened with a wrench. For example, when joining two furniture components, you can compare the bolt’s 40mm length with the material and hardware it needs to pass through before starting assembly.

It suits you if the specified dimensions, full thread, and black finish fit the job. You may want to skip it if you need a different length or head style, or if the application requires a stated strength rating that isn’t provided here. A different bolt may be a better choice when the fit or performance requirements call for specifications beyond size and material.

Box contents

The package includes 20 M6 x 40mm hex head bolts. That gives you a set for a project using several matching fasteners, or spares for routine repairs. The listing does not mention nuts, washers, a wrench, or other hardware, so plan on sourcing those separately if your assembly needs them.

The product description identifies the bolts as 18-8 stainless steel (304) and says they have a black coating. Stainless steel is presented as corrosion-resistant, but no specific environment or coating test is described. For outdoor, wet, or otherwise demanding use, the listing alone does not establish how the finish will hold up in your conditions.

Before you decide

Are these bolts fully threaded? Yes. The product description specifies a full thread.

What wrench or special tool is needed? The listing says installation requires a wrench and does not call for special tools. It does not specify a wrench size.

Are nuts and washers included? Only 20 bolts are listed as included. Nuts and washers are not mentioned.

Is it worth it?

This set is worth considering when the job calls for the exact M6 x 40mm size, full threading, and a black-coated stainless-steel finish. The 20-piece quantity is useful for projects that need multiple matching bolts, while the hex head offers a straightforward wrench-based installation approach. Compared with choosing a more basic fastener by appearance alone, checking the thread pitch, length, and head dimensions here gives you concrete details to match against your assembly.

The main limitation is the missing performance information: there is no stated load capacity, torque guidance, or detail about the coating’s durability in a particular setting. Without having tried it, the sensible call is to buy it for a size-matched furniture, woodworking, or general repair task—not to treat the material description as proof that it fits every high-stress or corrosive environment.