Pete.
Member
- Messages
- 14,098
- Location
- Kent, UK
Pete your showing grinding wheels mate by the look of it.
They only fit one way and are built different to cutting discs.
The second one is a grinding wheel yes but the first pair are dished centre cutting discs you can just read the 2.5mm thickness.
All of my other grinding wheels have a metal ring both sides BTW.
EDIT: thickness