GRK R4 ProPak Multipurpose Screws, 10 by 3-1/8-Inch, 350-Count : Amazon.com.au: Home Improvement
GRK #12, #14 x 5-5/8-inch Star Drive R4(TM) Multi-Purpose Framing Screws - 50 pcs | The Home Depot Canada
GRK #9 x 3-1/8-in Polymer R4 Exterior Wood Screws (720-Per Box) in the Wood Screws department at Lowes.com
Grk Fasteners Part # 100137 - Grk Fasteners #10 X 3-1/8 In. Star Drive Bugle Head R4 Multi-Purpose Wood Screw (210-Pack) - Wood Screws - Home Depot Pro
GRK #9 x 3-1/8-in Polymer R4 Exterior Wood Screws (720-Per Box) in the Wood Screws department at Lowes.com
GRK R4 ProPak Multipurpose Screws 10 by 3-1/2-Inch 300-Count : Amazon.com.au: Home Improvement