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Hi-Lo Self Tapping Screws


These specially threaded screws are designed to cut threads as they are driven into untapped holes in a variety of low density materials (plastics, wood, masonite and particle board).

Hi-Lo self tapping screws have a double lead thread where one thread is high and the other low for easier penetration into the substrate. The high thread is sharper than a conventional thread. The sharp high thread causes less displacement of material when it is driven into the substrate. Consequently, it requires less effort to drive into material. In addition the greater amount of material remaining in between the high threads, the smaller minor diameter thread increases contact with the substrate resulting in a stronger grip and increased resistance to pull out and vibrational loosening forces.

These screws are available in carbon steel in a number of finishes (clear zinc, black zinc,black oxide) and stainless steel. Available in a variety of head styles (flat, hex washer, pan and truss) and drives (phillips, slot, 6-lobe, hex) Available in sizes from #2 to #14 diameters and lengths from 3/16" to 2".

If you should happen to be looking for Hi-Lo self tapping screws or other fasteners that are currently not listed as stock items on Aspen Fasteners, or in the event that we are out of stock, we will do our best to find the parts for you. All of the Hi-Lo self tapping screws listed in zinc or black oxide are standard stock items, and available for immediate same day free shipping.

All items are available in bulk quantities, but if smaller quantities are preferred, we would like to hear from you as we are often able to offer the same parts in smaller package quantities. If you require a quote for a specific fastener or Hi-Lo self tapping screws listed or not, please call us at 1-800-479-0056 or email us at and one of our knowledgeable sales staff will help you with your needs.

The price of any fastener or Hi-Lo self tapping screws listed on the site includes shipping to your destination. If you have any special shipping requirements (eg expedited/next day delivery), please let us know at the time of order placement and we will make the necessary arrangements. Discounts are available for larger quantity orders. Major credit cards are accepted.