R4 Screw 5.0 x 100 (10 x 4") Stainless Steel
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The R4 screw features self-countersinking cutters. It can be used in hard and soft woods without drilling a pilot hole. Screw head top closes the hole exactly, leaving no damaged fibres around the wider area of the head.
Most hardened stainless steel screws are made of low grade #400 stainless steel; which provides only limited corrosion protection. By comparison, Pheinox stainless steel screws are made of a hardened #305 or #316 material.
Pheinox screws are hardened and come with a lifetime anti-corrosion warranty. GRK's special composition PHE stainless steel is one of a kind. It is hardened and rust free!
A screw is a screw, right? .... Think again!
GRK Screws are considered to be the finest in the world, both in quality of materials and conceptual engineering. GRK screws are designed for use in decks and other industries using hard or soft woods. Their uses are almost unlimited due to their superior qualities. A special hardness is achieved through a fine tuned heat treatment process that makes GRK screws virtually unbreakable.
GRK screws can considerably reduce total installation or assembly time. They are easy to install, as no pushing is required to keep the bit in the head of the screw; which also means that there are no cam out problems and there is less friction due to their lubrication. GRK screws back out as easy as they go in and do not suffer from head twist off, strip out or screw breakage; problems that most contractors encounter every day.
GRK screws can actually save you money by reducing installation time and eliminating waste.
Design Features
-W-cut threads "crush" the wood rather than splitting it as do traditional screws. A regular screw acts as a wedge, splitting the wood apart and increasing the risk of cracks and splits on the surface. A GRK screw crushes the wood into itself, which means no predrilling required, a smoother entry even close to the edge, and a better long-term grip by the wood. Where traditional screws may actually loosen overtime as the wood shears away, with GRK screws, the wood actually re-expands gradually overtime, "gripping" the screw firmly.
-GRK's Zip Tip is designed for fast starts in any fibrous material.
-GRK's unique Climatek Coating has successfully survived over 20 "Kesternich" cycles. Each Kesternich cycle equals 12-14 months of exposure to heat, cold, wind, water, salt and other weather-related stresses. Climatek Coating also withstood 1000 hours of salt spray testing, making it the most durable coating of its kind. It is also the only coating of its kind to combine long term rust protection with an attractive golden appearance that blends in perfectly with wood.
-Teflon-coated threads allow the screw to enter smoothly into the wood, reducing the torque and therefore the effort required by the user.
-A Star Head prevents stripping and reduces stress on the user. Since no force is required to push the screw into the wood, GRK screws can be used comfortably at any angle.
-Pheinox stainless steel screws provide a reasonably priced alternative when only stainless steel will do. Pheinox screws are hardened and come with a lifetime anti-corrosion warranty. GRK's special composition stainless steel is one-of-a-kind. It is hardened and rust free!