The Contour Sander fits any standard 115mm (4 1/2") or 125mm (5") angle grinder. However, when choosing an angle grinder to suit the blade, you should look for the following features:
- An auxiliary handle to ensure easier balance, manage and control. Using the handle when carving not only improves user comfort and visibility but increases user safety. 
- A metal guard that can be rotated and fixed to 45 degrees
- On/Off switch to be positioned on the top or side 
- 550 Watts power, at a minimum 
- Should have a spindle thread of: 
- M14 (AUS and UK) |  M14 (Europe) | 5/8″ (North America)
 If you need an M10 Adaptor Nut click here.
The Contour Sander can be used on a variable speed, cord, or cordless grinder, as long as it runs at a speed of 9000 RPM or higher. 
Possible cause: Incorrect thread or adapter
 Solution: Check thread, locate the correct adapter
- In Europe the shafts suits an M14 thread
- In North America, the shaft suits a 5/8″ UMC x 11 thread
- In Australia the shaft suits an M14.
Possible Cause: Excessive flexing of the rubber pad in deep contours
 Solution: Use a plastic flange to hold either the paper or cloth discs.
Possible cause: Shaft axis not aligned correctly with grinder spindle
 Solution: Check that the extension shaft has fully tightened to the base of the grinder spindle. Do not use the base collar nut that is usually used to locate a grinding disc.
Possible Cause: Grinder spindle not accurate 
 Solution: Try on another grinder