DEWALT DW8570B5 7'' Extreme Diamond Edge Cutoff Wheel-30x Life (5 pieces box)

If you buy this, once you mount, you will probably won't change the disc again. Since this is not abrasive, cutting speed is less, finish is not appealing. Keeping limitations aside, it doesn't create dust, it doesn't get shorter (non consumable) perfect choice for those who use angle grinders with "angle grinder stand". So this is an one time investment for DIYers.

Another good product by DeWalt.

DeWalt acquired Lenox a few years ago. These are basically rebranded Lenox MetalMax wheels.Since it doesn't wear down like the regular abrasive wheels, it is very convenient. You can permanently fix this wheel on one of your grinders and use it for a long period.Compared to an abrasive cutting wheel, this is much safer option. The possibility of the wheel exploding is very less.It can also be used to cut a verity of materials like mild steel, stainless steel, aluminum, wood, PVC, and other soft materials. Normal abrasive wheels are not good to cut aluminum and wood.Plumbers and electricians are going to love it because this one wheel can be used to cut almost anything.However, it has a lot of drawbacks.1) The cuts are very slow compared to abrasive wheels. It takes almost double the time.2) It produces very rough cuts. See the picture where I am comparing the quality of the cuts produced by the diamond wheel and an abrasive wheel on a 6mm steel plate.3) It is very loud while cutting. Please use some sort of hearing protection while using it.4) More powerful angle grinders are needed for this wheel. On grinders less then 1000w the cuts are going to be painfully slow.5) Expensive.

I am already used 14" diamond cutoff wheel DeWalt wery nice so I purchased 7 inch wheel now .