What is the max temperature a gator bite coupling will take

I believe they are rated for 180 degrees. Why do you ask? They will work just fine for any residential domestic hot water applications, however, if you are thinking of using them on a hot water heating system (for space heating with baseboards), I would suggest against it as baseboard heat usually runs between 180 and 190, which is on the high side of the max for these fittings.