M8 x 1.25p x 16.3 Metric Coarse G304 Stainless Nutsert Countersunk Round Open Splined Grips 0.5-3

About Round Open End Nutserts

Round Open End Nutserts are the most common rivet nut style: a round body in a standard pre-drilled round hole, open at the back so a longer bolt can pass through. Installed with a nutsert tool that crushes the body behind the panel to clamp the joint. Default choice for general sheet-metal fixing in vehicles, machinery, enclosures and panels where the bolt depth isn't constrained by the back face.

Which tool sets this nutsert?

An M8 nutsert is set by these tools: FAR KJ21 · POP PNT210 · RT-512 · Geiger GHTH3. Stainless nutserts are harder to set - use a ratchet tool (PNT210 or RT-512); plier tools suit aluminium and smaller steel sizes. See the full Setting Capacity by Tool reference for the per-material (aluminium / steel / stainless) breakdown.

Frequently Asked Questions

Material & Coating

Stainless A2-70 G304 Austenitic stainless steel. Property class 70 designates a minimum tensile strength of 700 MPa with a 0.2 percent proof stress of 450 MPa. Lightly magnetic in cold-worked form, which does not affect corrosion performance.

Grade selection A2-70 G304 is the general-purpose stainless grade for outdoor and most chemical environments. A4-70 G316 contains 2 to 3 percent molybdenum, giving substantially better resistance to chlorides; A4-70 G316 is the preferred grade for marine, coastal and pool environments.

Important Do not pair stainless fasteners with plain or galvanised steel components in wet service. The galvanic potential difference accelerates corrosion of the less-noble metal.

Class Stainless fasteners are classified by property class: A2-35 / A2-50 / A2-70 in G304 stainless, and A4-40 / A4-70 / A4-80 (Bumax 88) in G316. The first digit indicates the alloy and the second is the minimum tensile strength in 100 MPa increments (e.g. A4-70 = 700 MPa). See the head marking chart and full strength table.

Thread Pitch & Terminology

Thread Pitch (Metric) Metric fasteners measure thread pitch as the distance between thread peaks, expressed in millimetres. Every nutsert we stock is metric coarse - the default series that matches standard metric bolts and machine screws. This product has a 1.25mm coarse pitch, meaning the peaks are 1.25mm apart.

How is the Length of a Nutsert Measured?

Nutsert Length Every nutsert is measured the same way: overall, head included - from the top of the head to the end of the body. The rule holds for every head style we stock, whether it is a large flange, small flange or countersunk head.

Length alone does not pick the right nutsert. The Grips range in the product name (for this product: 0.50 - 3.00mm) states the panel-thickness window the body clamps on - match that to your panel thickness and the body length looks after itself.

Resources

Pricing & Delivery

Includes GST, a Tax Invoice and Free Standard Delivery anywhere in Australia.

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Disclaimer

Technical data Researched and compiled from numerous industry sources for the sole purpose of providing basic information. All material is advisory only and its use by anyone is entirely voluntary. Reliance on it for any purpose by anyone is at the sole risk of that person, and Bolt and Nut Australia is not responsible for any loss, claim or damages arising therefrom. In developing this information, Bolt and Nut Australia has made a determined effort to present it accurately.

Measurements Sizes are taken from supplier catalogues or hand-measured and should be used as a guide. Minor variation between batches is normal. Stock is sourced from various suppliers, so differences may exist between batches in thread length, markings, appearance or finish.

Product Photos & PDF Data Sheets Represent the product type, not exact size. PDFs are a reference guide only. Specifications may change without notice.

If you see any problems with any of our specifications or you require additional information please contact us.