A: The chargers are not universal. You would specifically need one that charges 20v batteries for DEWALT
A: The model number for the hard kit box is N153976.
A: A 7 1/4 blade would not be compatible with this saw.
A: We haven’t had any problems. Ours does a great job
A: Please contact us at WECARE@SBDINC.COM so that we may assist you further with this matter.