1,15years professional manufacture 2,TCT,Bi-mental,HSS hole saw 3,cutting wood,steel 4:size14~380mm 5:export toUSA, ... steel and spring steel;3.Adopt imbalanced scale-saw and lateral teeth design,with characteristics of rapid trepan boring,fast slug clearance ... -3/8"S1-2102108-17/64"S1-64642-1/2" Bi-Metal hole saw