Hello Rooky, the Milwaukee 4-1/2 in. x 0.045 in. x 7/8 in. Cut-Off Wheel will work on the 7.0 AMP 4-1/2" Small Angle Grinder.
Be very careful when using abrasive wheels such as these when cutting aluminum alloys as these alloys have strong tendencies toward clogging up the spinning wheel and can lead to grabbing / shattering of the wheel at rpms. Aluminum can be cut with a carbide tipped saw blade with excellent finish results as we always did in an aluminum handrail plant for decades. You may have noticed how aluminum clogs up sandpaper well before it is completely worn ( now imagine the same effect with high rpm spinning wheel ). So, if You do use these watch for it and stop on the aluminum and cut a little scrap steel / stainless to clean the wheel and work slowly as needed and a full face shield & leather shop apron is always advised for any cut-off wheel operation. I could not help but comment on this as former safety team leader in the facility and people can be seriously injured by shrapnel from high rpm shattered wheels. Keep Your work secure and safe!
Yes, this will fit model #6140-30