The backer pads that come with a polisher when you purchase it are usually a hard rubber. They are supposedly flexible, but they are designed for granite, not concrete. They are too hard, and instead of flexing will just scallop the concrete.
 
In order to polish curved surfaces, such as inside sinks, you need a very flexible backer. By using this 4″ backer with 5″ diamond pads, you are able to polish tighter curves without risking gouging the concrete.
 
A thick foam 3″ backer does not flex uniformly. Where the larger pad meets the edge of the backer, there is a pressure point that gouges the concrete. A small, 3″ backer also tends to lose grip on 5″ pads. Our very thin, very flexible 4″ backer securely grips the polishing pad and allows it to flex more uniformly and produce a better quality surface.
 
This backer can be used with any polisher with standard threads, just like the 5″ and 7″ backers.

Granite Marble Stone Floor Tile for Flooring and Wall

Color:  White, Black, Grey, Coffee, Yellow, Red, etc.

Common size of Granite & Marble tiles:

12" X 12" or 305 X 305mm

16" X 16" or 400 X 400mm

18" X 18" or 457 X 457mm

12" X 24" or 300 X 600mm

24" X 24" or 600 X 600mm

Thickness:  10mm, 12mm, 15mm, 18mm, 20mm, 30mm,etc.

Thickness Toleranc:   +/- 1mm,or +/- 2mm,Polished 85 Degree Up.

Usage:   Used For Tile, Granite Tile, Flooring Tile, Granite Slab, Marble Slab, Wall Cladding Tile, Momument, Countertop, Kitchentops, Steps, Kerbstone, Paving Stone...etc.

Finish:   Polished, Honed, Flamed, Sandblasted, Rough Hammered, Bush Hammered, Mushroom, etc.

Edge Finish:   Bevel, Straight, Bull-nose, Round Edge,etc.

Granite Tiles:

Granite is one of the hardest and most durable of all flooring tiles. Granite tile is a perfect choice for hard surface applications where durability and low maintenance is important, such as tiles for kitchen countertops, high traffic floors and tile flooring for commercial applications.

Marble Tiles:

As an elegant & high-end building material,is widely in many housing areas.we invite you to enjoy this visual feast and aunderstand marble interior flooring better.