Tool AidSG 91900 Extra Long Flat Chisel

They say the shank is .401" , why it doesnt fit in my air hammer 114GQC, which is for .401" bits?

wiil it fit a regular small air hammer. i beleve my bits are 3/8 and i need it for concret, will this work for me?

What is width of tip?

Does this tool fit a ingersoll rand 114gqc? i saw it was suppose to, but it won't go into mine. the shank from the shoulder to the end is too long.