Alpha® Flexible Backer PadsAlpha® Flexible Backer Pads are the hook-and-loop carrier behind Alpha’s wet polishing system — the preferred choice for stone fabricators, tile contractors, monumentalists and restoration crews. The pad body is engineered to flex through tight contours and inside curves so polishing discs, sandpaper and felt wheels stay in full contact with the work piece. Available in 2", 3", 4" and 5" diameters with 5/8"-11, M14 or M16 threads, the pads fit virtually every popular wet polisher and variable-speed grinder.Features Hook-and-loop face holds polishing discs, sandpaper and felt wheels securely Highly flexible body conforms to contours, inside curves and tight radii Available in 2", 3", 4" and 5" diameters Thread options: 5/8"-11, M14 and M16 Maximum rated speed 6,000 RPM (run below 4,000 RPM in service) Built for daily production use with extended pad life Designed for wet polishing only — requires water feed Fits Alpha® AIR-680, VSP-320 and most popular polishers and grinders .dst-accordion { margin-top: 25px; border: 1px solid #FDDCC5; border-radius: 6px; overflow: hidden; } .dst-accordion-item { border-bottom: 1px solid #FDDCC5; } .dst-accordion-item:last-child { border-bottom: none; } .dst-accordion-toggle { display: none; } .dst-accordion-label { display: flex; justify-content: space-between; align-items: center; padding: 14px 20px; cursor: pointer; font-size: 17px; font-weight: 700; color: #231F20; background: #fff; transition: background 0.2s; } .dst-accordion-label:hover { background: #FFF3EB; } .dst-accordion-label::after { content: '+'; font-size: 22px; font-weight: 700; color: #F15C22; transition: transform 0.3s; } .dst-accordion-toggle:checked + .dst-accordion-label { background: #FFF3EB; } .dst-accordion-toggle:checked + .dst-accordion-label::after { content: '\2212'; } .dst-accordion-content { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; padding: 0 20px; background: #fff; } .dst-accordion-toggle:checked ~ .dst-accordion-content { max-height: 5000px; padding: 15px 20px 20px; } Models / Part Numbers Part No. Size Thread Type Max RPM UPC GP25/8PD 2" 5/8"-11 Flexible 6,000 RPM 749173461316 GP35/8PD 3" 5/8"-11 Flexible 6,000 RPM 749173520235 GP3M14PD 3" M14 Flexible 6,000 RPM 749173520266 GP3M16PD 3" M16 Flexible 6,000 RPM 749173520280 GP45/8PD 4" 5/8"-11 Flexible 6,000 RPM 749173520389 GP4M14PD 4" M14 Flexible 6,000 RPM 749173520419 GP4M16PD 4" M16 Flexible 6,000 RPM 749173520433 GP55/8PD 5" 5/8"-11 Flexible 6,000 RPM 749173520532 GP5M14PD 5" M14 Flexible 6,000 RPM 749173520563 GP5M16PD 5" M16 Flexible 6,000 RPM 749173520587 How to Use Choose the pad diameter to match (or slightly under) the polishing disc you plan to mount. Verify spindle thread on your polisher and select the matching 5/8"-11, M14 or M16 pad. Thread the pad onto the polisher spindle hand-tight, then snug with a wrench. Press the hook-and-loop polishing disc onto the pad face, centered and fully seated. Connect water feed and confirm steady flow before starting the tool. Operate at or below 4,000 RPM; on high-speed grinders use only variable-speed models that can be slowed below that limit. For tight radius work, use an undersize pad so the abrasive can conform to the curve. After use, rinse the pad, hang to dry, and inspect the hook face for wear or contamination. Specifications by Variant 5/8"-11 thread — 2" Flexible Backer Pad — GP25/8PD Part No. GP25/8PD UPC 749173461316 Type 2" Flexible Backer Pad Attachment 5/8"-11 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.30 lbs Package Dimensions 4.5" x 3.5" x 1.5" Commodity Code 8466.91.0000 Country of Origin Japan 5/8"-11 thread — 3" Flexible Backer Pad — GP35/8PD Part No. GP35/8PD UPC 749173520235 Type 3" Flexible Backer Pad Attachment 5/8"-11 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.30 lbs Package Dimensions 4.5" x 3.5" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan M14 thread — 3" Flexible Backer Pad — GP3M14PD Part No. GP3M14PD UPC 749173520266 Type 3" Flexible Backer Pad Attachment M14 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.30 lbs Package Dimensions 4.5" x 3.5" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan M16 thread — 3" Flexible Backer Pad — GP3M16PD Part No. GP3M16PD UPC 749173520280 Type 3" Flexible Backer Pad Attachment M16 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.30 lbs Package Dimensions 4.5" x 3.5" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan 5/8"-11 thread — 4" Flexible Backer Pad — GP45/8PD Part No. GP45/8PD UPC 749173520389 Type 4" Flexible Backer Pad Attachment 5/8"-11 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.40 lbs Package Dimensions 4" x 4" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan M14 thread — 4" Flexible Backer Pad — GP4M14PD Part No. GP4M14PD UPC 749173520419 Type 4" Flexible Backer Pad Attachment M14 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.40 lbs Package Dimensions 4" x 4" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan M16 thread — 4" Flexible Backer Pad — GP4M16PD Part No. GP4M16PD UPC 749173520433 Type 4" Flexible Backer Pad Attachment M16 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.40 lbs Package Dimensions 4" x 4" x 1.25" Commodity Code 8466.91.0000 Country of Origin Japan 5/8"-11 thread — 5" Flexible Backer Pad — GP55/8PD Part No. GP55/8PD UPC 749173520532 Type 5" Flexible Backer Pad Attachment 5/8"-11 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.60 lbs Package Dimensions 5" x 5" x 1.5" Commodity Code 8466.91.0000 Country of Origin Japan M14 thread — 5" Flexible Backer Pad — GP5M14PD Part No. GP5M14PD UPC 749173520563 Type 5" Flexible Backer Pad Attachment M14 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.60 lbs Package Dimensions 5" x 5" x 1.5" Commodity Code 8466.91.0000 Country of Origin Japan M16 thread — 5" Flexible Backer Pad — GP5M16PD Part No. GP5M16PD UPC 749173520587 Type 5" Flexible Backer Pad Attachment M16 thread Recommended For Wet polishing with hook-and-loop polishing pads Packaged Weight 0.60 lbs Package Dimensions 5" x 5" x 1.5" Commodity Code 8466.91.0000 Country of Origin Japan Common Specifications Property Detail Maximum Speed 6,000 RPM (operate < 4,000 RPM) Application Wet Polishing Only Backing Hook & Loop Thread Options 5/8"-11, M14, M16 Diameters 2", 3", 4", 5" Country of Origin Japan Related & Companion Products Alpha® Ceramica Resin Polishing Discs Alpha® Ceramica EX Polishing Discs Alpha® VSP-320 Variable Speed Polisher Alpha® AIR-680 Air Polisher FAQs What sizes and threads are available?2", 3", 4" and 5" diameters in 5/8"-11, M14 or M16 thread.What tools are these pads designed for?Hand-held wet polishers such as the Alpha® AIR-680 and VSP-320, plus any variable-speed grinder that can run below 4,000 RPM with matching thread and water feed.What is the maximum operating speed?Do not exceed 4,000 RPM in service. The pads are rated to 6,000 RPM but pad life and safety improve dramatically below 4,000 RPM.Can I use these on a high-speed angle grinder?Only if the grinder is variable-speed, can be slowed below 4,000 RPM, has the matching spindle thread and an external water feed.How do polishing discs attach?The pad face is hook-and-loop — press hook-backed polishing discs directly onto the pad.Which pad should I use for a tight radius?Choose an undersize pad so the polishing disc can wrap and conform to the radius.Are these pads for wet or dry polishing?Wet polishing only. Running them dry will damage both the pad and the abrasive.How should I store the pads between jobs?Rinse off slurry, hang the pad to air-dry, and keep the hook face free of grit and debris. VideosNo product-specific videos are currently available from the manufacturer or DST. Documentation 📄 Backer Pads — How To Use 📄 Alpha® Warranty Information ⚠ WARNING: Cancer and Reproductive Harm — www.P65Warnings.ca.gov. Always wear appropriate PPE.
