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Bi-Flex® 300 Series Stainless Steel Self Drilling Fasteners

Any construction project has the same core demands that must be met. Structural integrity and longevity are a must. Workmanship and productivity must be on par. Cost effectiveness has to be a priority. All of these demands the skills and expertise that lies within the construction industry. To meet these requirements, it means relying on products and materials that can perform without compromise.

Power Bolt and Tool has the knowledge of what the construction industry relies on for success and has taken on the responsibility of meeting the demand by providing easy access to products such as the Bi-Flex 300 Series Stainless Steel Bi-Metal Self Drilling Fasteners.

Whenever a project is to be completed in locations that are comprised of damp wet conditions, and are at the mercy of the elements, then the Bi-Flex 300 should be the metal fastening system of choice. It is the ideal Elco metal fastener for a variety of mediums such as composite panel systems either aluminum or steel. They have no difficulty in their application to ACQ treated wood to steel. They are the prime choice for brick veneer or solar panel anchoring. Whenever there is a risk of corrosion then you can rely on this metal fastener to stand up to whatever moisture it is going to be exposed to.

The Bi-Flex 300 Series Stainless Steel Bi-Metal Self Drilling Fasteners is one of the top performing metal construction fasteners that has the responsibility of producing longevity in any completed construction project that is comprised of metal. It provides the customer of the project with a finished structure that is going to retain its integrity for many years to come and be aesthetically impressive.

The tradesmen and construction companies that utilize these Elco metal fasteners are going to be able to take pride in their workmanship, expedite their application, and reduce waste. The responsibility of these bi-metal sell drilling fasteners even resorts back to the architects, who have to draft plans for structures that are going to be structurally sound when it comes to the attachments of the metal materials that will be used in the projects.

For projects that are within an aggressive environment such as damp wet areas, it means using a metal fastening system that is going to be immune to the damage this type of setting can create. The Bi-Flex 300 is specifically made for this type of project.

In order for these metal fasteners to be able to perform to the expectations placed upon them and continue to uphold the impeccable reputation of all Elco metal fasteners, they rely on the materials and design that they are comprised of.


One of the biggest threats to any fastening system is uniform corrosion which is easily identified with the red rust on steel residue. There is the problem of galvanic corrosion in conjunction with dissimilar metals. Then there is delayed embrittlement that has to be addressed which creates the risk of “head popping” of inferior fasteners. The solution to all of these lies within the materials that the Bi-Flex 300 Series Stainless Steel Bi-Metal Self Drilling Fasteners is made with. They are made with the 300 series stainless steel and then fully coated with the Stalgard® Galvanic Barrier. This combination of materials creates a multi-level corrosion resistance that simply cannot be matched. They are impressive in their strength and ductility and are known for their reliability.

Why settle for partial corrosion protection for just one of the three potential threats, when you can rely on a metal fastening system that can offer full protection. There are some alternative fasteners that are efficient in performance against one type of corrosion such as uniform corrosion but are not able to stand against HAS CC failures. Or there are other types that require special plating to delay some types of corrosion. For full corrosion protection, productivity in work performance, superior project completion and cost effectiveness it means the application of the Bi Flex300.

Working in conditions that demand the need for anti-corrosive metal fasteners creates the type of atmosphere that is difficult to work in. With the ease of drill and tap application into components made of structural steel or aluminum to a max. of ½” thick, the Bi-Flex 300 Series Stainless Steel Bi-Metal Self Drilling Fasteners makes quick work of any project. Precision can be counted on with the hardened fused self-drilling tapping point. There is a large selection of sizes and heads to meet the demands of most projects. Its flexibility of being able to comply with creating the strength and corrosion resistance plus create an impressive looking finish is what makes tradesman favor this fastener.

With these Elco metal fasteners leaving nothing to be desired in the construction field, it means that the demand for them to be available has to be met. Power Bolt and Tool knows the importance of construction jobs from start to finish, and how delays in product availability cannot be an option. When those working on projects need the Bi-Flex 300 Series Stainless Steel Bi-Metal Self Drilling Fasteners, they don’t have to look any further than Power Bolt and Tool both for quantity and choice of size.

Before we begin providing you information on the Drilling Screw called Bi-Flex, we would like to ask you some questions:

  • Have you ever remodeled a building or house where the screws were in such bad shape that they were literally breaking off?
  • Have you ever come across screws that broke when all you did was pull lightly on a material or surface?
  • Have you ever heard of something falling off because the wrong screws were used for the wrong application?

Well, we have, and we’re sure that most of you have as well! It would surprise you to know about the many stories where contractors were sued or faced an investigation for using the wrong type of fasteners for the wrong application. This is exactly why we wanted to inform you about the application of the Bi-Flex screws. Not only do these fasteners not break from delayed embrittlement failures, but also provide longer life cycles for buildings. These screws also offer extended warranties. All these results in a greater performance. So we wanted to provide you with detailed information on why and where the Bi-Flex fastener should be used. This incredible fastener from Elco, called the Bi-Flex Screw or Bi-Metal fasteners, promises to provide incomparable life cycle for buildings. Also, it does not break regardless of its usage.

This drilling screw has the corrosion resistance of 300 series stainless steel. In addition, Bi-Flex has the efficiency of very strong drill screws. Bi-Flex is made of the 300 series (18-8) stainless steel alloy to provide unmatched corrosion resistance for the most extreme and even the toughest of applications. The fastener has a fused and hardened steel drill point and lead threads that can quickly drill and tap structural steel and aluminum that is up to a whopping ½” thick.

Bi-Flex screws are coated with Elco’s famous silver-colored Stalgard® GB, which protects aluminum components from accelerated corrosion when in contact with stainless steel. These drill-screws, made from a 300 series stainless alloy, it basically makes them virtually immune to delayed embrittlement failures that you would tend to see with 400 series stainless self-drilling fasteners.

To summarize, major features of Bi-Flex screws are:

  • Bimetal technology; 300 (18-8) stainless steel head and shank.
  • Fused and hardened steel drill point.
  • Silver-colored Stalgard® GB coating.
  • Available in a wide variety of sizes and head styles.


First and foremost, when you use Bi-Flex screws, you can rest assured that the fasteners will not break off from delayed embrittlement failures. The benefits, however, do not stop here. The Bi-Flex drill-screw has high strength, substantial ductility, and very high reliability. It holds an outstanding corrosion resistance and a really long service life.

So, now let’s tell you about another one of Bi Flex’s unique features, one that no other drill-screw has. Bi-Flex screws are virtually immune to delayed embrittlement failures. These are ideal for windows, among many other things; and that is not all. If you understand the concept of galvanic compatibility in dissimilar metal, then you would understand that drilling a stainless steel screw with another metal such as aluminum is akin for galvanically attacked. With Bi-Flex screws, you have a greater galvanic compatibility in dissimilar metal applications involving aluminum.

Another great benefit of the Bi-Flex is that these can be quickly drilled and tapped into steel or aluminum, like a hot knife through butter. You are looking, as mentioned earlier, at drilling into ½” metal thickness, that too with ease.

Lastly, these screws provide high in-place value over the life of structures, components, and systems.


  • Exposed anchoring/ coastal/ aggressive environments.
  • Curtain wall/window wall systems/ rain screen systems.
  • Perfect for windows, doors, awnings and thresholds.
  • Panel systems for steel or aluminum framing.
  • Aluminum enclosures.
  • ACQ-treated wood.
  • Brick veneer anchoring.
  • Solar panel systems.

We can honestly promise you that you will not find a better, easier-to-install and more reliable screw for even the toughest of construction applications than Elco’s line of Bi-Flex screws or fasteners.


The Bi-Flex screw is a high valued item, and this has. Unfortunately, led to many people putting the wrong screws in boxes and passing them off as Bi-Flex. So to make sure you have received the right self-drilling screw, here is a picture and a list of the characteristics to look for and identify Bi-Flex screws:

The head markings of the genuine Bi-Flex screws consist of:
Number “3” above the Elco logo as shown below:

There are distributors that sell Bi-Flex screws. Not a lot of companies tend to hold them in stock, except for Power Bolt and Tool. Because this is a premium drilling screw, people usually tend to select a cheaper alternative, such as 400 series stainless self-drilling fasteners. Sadly, many of these individuals do not understand that 400 series stainless fasteners do rust and are not protected from delayed embrittlement failures. Using these fasteners is like having a time bomb applied to something, hoping it will not explode anytime soon.

If a 400 series stainless drilling screw is used for the wrong application, it could break within seconds. It might last for some years. One day or the other, it will eventually break; it is just a matter of time. Bi-Flex screws, on the other hand, will last.

If you have any questions or you are just looking for more information on Bi-Flex fasteners or window screws, we recommend you contact our experts at Power Bolt and Tool by either calling at 1-888-514-5151 or by clicking on the right to select the expert you would prefer to talk to.

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