I do wish this tool included #4 dies. It was too big for my 1/2" OD diameter ferruled tubing. But the tool looks well made for the larger hoses. Note a 5/16" refrigerant hose has an outside diameter near 3/4" OD. This tool is large! Called Vevor and they would not could not tell me if #4 dies even existed for this tool. First agent wanted pictures of their own tool (duh). Second agent just said he could not give me or sell me anything. So I still wonder if #4 dies are even made. Probably not.