None were twin bores.
He indicated that based on the Radice pipes he has seen they use a much "stiffer and harder acrylic" than, say, Castello. He said: "I am extra careful when cleaning Radice stems and never do I use a drill bit to loosen material in the stems. I have had tenons shatter, buttons split, and holes just show up mid stem on Radice’s"Did he have any insights as to what may be the source of the stem issues?