A bevel or conical brush has a tapered face that sits in V-welds, fillets and angled joints a flat wheel can't get into.
They come in twist knot or crimped wire, steel or stainless steel. Most fit an angle grinder on an M10 or M14 thread, and the rest are on a 6mm shank for a drill or die grinder. Check the brush's max RPM against your grinder's no-load speed before you fit it, and the brush buyer's guide shows where to find both numbers.
