Timberwolf Silicon Steel 1/4" x 6 PC .025
After a lot of hard use it snapped, while I was not around. It surprises me that it did not break at the weld. Welding involves a lot of metallurgical trauma after all. Oh well, no matter, it was dull and should have been replaced last year. I'll probably order a Lennox bimetal of the same configuration. 3/8" might be better for all around use,,,,still thinking it thru.