GRK offers a complete line of fasteners in a wide variety of sizes and for many different applications. All of GRK’s products are unique, featuring at least one patent. Guided by its commitment to invention and quality, GRK continually aims to improve existing products and develop innovative new products for professionals and handymen alike.


Frame With Ease and Confidence
GRK’s R4™ self-countersinking screw is versatile. The screw has a patented underhead with saw-blade like cutting teeth and six self-contained cutting pockets. Together they act similar to a circular saw-blade, transporting the drill dust away from the edge of the screw and cutting clean into even the most brittle materials without cracking any surface treatment.

R4™ screws 2″ and longer have a four-threaded CEE Thread. This enlarges the screw hole for the non-threaded portion of the fastener, allowing the wood to settle. It increases the screw’s drawing strength and reduces the friction on the screw shank which in turn lowers the driving torque. The screws are used for wood, plastic, cement fiber board, particle board, sheet metal, wood decking, and melamine, and are available in a wide variety of sizes.


Easy-to-Install Lag Alternative
GRK’s RSS™ Rugged Structural Screw is made of specially hardened steel to create high tensile torque and shear strength. The sharp threads and points bite instantly into the material, reducing the splitting effect due to smaller shanks. The screws are ideal for anywhere you would use a traditional lag screw, without pre-drilling.  Approved for use in all applications that include treated lumber.

RSS™ screws which are 3-1/8″ and longer have a six-threaded CEE Thread that enlarges the screw hole for the non-threaded portion of the fastener, allowing the wood to settle and increase drawing strength. The CEE thread also reduces friction on the screw shank, which can result in lower driving torque and less likelihood of splitting the wood, making the RSS™ screw a speedy, efficient lag screw alternative.


Built-in Washer Head Presses Flush Against Any Material
GRK’s Cabinet™ screws are designed specifically for use in cabinet construction and installation. The screws are thin enough to prevent most material splitting, while providing sufficient strength to guarantee secure installation. The washer head design presses flush against any material surface.


For Plumb Installation of Doors, Windows or Cabinets
GRK’s adjustable Top Star™ shim screw allows you to install wooden doors or windows without the use of shims. This system reduces labor and creates a hassle-free adjustment to ensure plumb installation. Fine adjustments are as simple as the turn of a screw and can last even after years of use and settling.


Smallest Head on the Market for a Clean Finish
GRK’s Trim™ Head screws are an excellent choice for carpentry applications, deck rails, exterior/interior trim, window extension jambs and more. Trim™ Head screws have the smallest screw head available, which prevents most material splitting.


Reverse Threads Prevent Mushrooming
GRK’s RT Composite Trim Screw is modified with reverse threading under the head of the fastener. This technology makes the RT Composite™ ideal for use in composite and cellular PVC trim. The reverse thread helps the screw head disappear beneath the surface of the classic wood composite material.


Corrosion Protection for Harsh Environments
PHEINOX™ stainless steel screws maximize both torque and bending strength and are made from only the best grade of stainless steel wire, 305.

This self-countersinking screw has an under head with saw-blade like patented cutting teeth and six self-contained cutting pockets. Together these features act like a circular saw blade, transporting the “drill dust” away from the edge of the screw hole while cutting a perfectly clean hole into even the most brittle materials without cracking any surface treatment. This allows the fastener to be installed without countersinking into even the hardest woods. The screw head closes the hole off with precision, leaving no damaged fibers around the head.

GRK recommends PHEINOX™ 305 stainless steel screws for applications that require superior corrosion resistance in wet environments such as decks, boardwalks, pools and hot tubs. PHEINOX™ 305 stainless screws are also recommended for use with cedar, redwood and various other wood substrates that have higher acid content.


Speedy Lag Bolt Alternative With Immense Drawing Power
Ideal for use in anchoring to concrete applications including basement framing and sheds. Caliburn™ Concrete screws are professionally engineered fasteners with a patented thread design to drive the screw in pre-drilled concrete and similar applications. Caliburn’s uncompromised draw and pull-out strength make it possible to be used in jobs which previously required an anchor. The screw’s aggressive thread design affords it the ability to work within the same pilot hole numerous times without durability issues between the fastener or threads.


Hansen Marketing Services, Inc.

1000 Decker Road
P.O. Box 640
Walled Lake, Michigan 48390
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Customer Toll-Free Phone:
(800) 552-4877

Business Office: (248) 669-2323

Fax: (248) 669-5750