These European-manufactured tungsten carbide mortar rakes fit directly to the M14 spindle on 115 and 125 mm angle grinders. This item is 26 mm long.
Tungsten carbide mortar rakes are suitable for soft to medium strength mortar removal but will struggle with hard mortars, often encountered where poor quality repair work has previously been undertaken. In such instances, a diamond blade is probably the solution for removing the mortar joint.
A Z3 cutter rake will cut most aggressively so will be best for soft or crumbling mortar. By contrast, it is likely a Z6 cutter rake will provide smoother operation on harder mortars, even though it may not cut any faster.