M5 x 0.80p Metric Coarse Zinc Yellow (8mm AF) Hex Phillips Sems Bolt Class 4.6 Low Tensile

About Sems Bolts

Sems Bolts are pre-assembled fasteners with a captive washer that cannot be removed once installed. The shank is rolled after the washer is fitted so the washer rotates freely but cannot fall off. Used on production lines and in field service where the assembler must not lose the washer. The captive washer is typically a flat washer, a spring washer, or both, depending on the part number.

Recommended use Indoor and dry-environment automotive, machinery, agricultural and electrical assembly where the yellow finish is specified by design or matches surrounding hardware.

Frequently Asked Questions

Material & Coating

Zinc Yellow Electroplated zinc on carbon steel with a yellow chromate passivation. A thin (5 to 12 micron) zinc layer applied by electrolysis, then dipped in a chromate bath that produces the iridescent yellow / gold appearance and slightly improves corrosion resistance over clear-passivated zinc.

Important NOT suitable for outdoor, wet, marine or treated-timber applications. The chromate layer extends salt-spray performance modestly over bright zinc but does not protect against prolonged moisture or chloride exposure. For outdoor use, specify hot-dip galvanised.

Class Metric fasteners are classified as class 2, 4.6, 8.8, 10.9, 12.9, 14.9. 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. Metric also branches into three series: coarse (the default; widest tolerance, easiest to tap), fine (a tighter pitch for higher clamp load or thinner walls), and extra fine (the tightest pitch, used for thin-wall tube, precision instruments, and aerospace fittings where vibration loosening must be minimised). Always match the series as well as the size - a metric fine nut will not engage a metric coarse bolt of the same diameter, and an extra fine nut will not engage either. This product has a 0.80mm coarse pitch, meaning the peaks are 0.80mm apart.

How to Measure

Fastener Length This product has a head that sits on top of the material, so the length is measured from directly under the head to the tip of the thread. The head itself is not included in the size.

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.