PeteG

Yep it's just the 1 hole. I've found a 120mm SDS Plus diamond bit on Ebay for @ $25. There will be some chiselling out as mentioned above

I need to drill a 120mm hole through a (dis-used) brick chimney brest, which has an outer layer of plasterboard & tile (@ 2cm), as an outlet for an air -con hose. With a suitable (120mm diamond tipped) stone cutter, would you say a Milwaukee SDS Plus (M18CHPX) is up to the job? I don't know if the chimney is built with 1 or 2 layers of brick, so the total depth-of-cut could be anywhere between 4-7 inches. I'm pretty sure my 18v Milwaukee drill would struggle; I've used a 100mm wood holesaw on it & there was noticeable vibration with all the torgue. Thanks.