Review on 🔩 AccusizeTools Straight Capscrew Counterbore 509S 0007 by Jeffrey Sanders

Purchased in November, just got around to using it. They cut well, used 3/8" a few times. Used 5/16" about a dozen times, all mild steel. The CB 5/16" shank broke just above the chip flutes. When changing the collet, it fell about 5" into the vise and just broke. I have been a toolmaker for 27 years and have never experienced anything like this. Do you offer replacement?