Old style 13RM cutters restrict flex radius. The new chromed cutters have a minor modified front and back edge profile and therefore swing a bigger angle/tighter radius.. They are marked with a "C" and may be suitable for chainsaw carving use, though the 13RMS has a shorter cutter specifically for that purpose..... New stihl spinner bit in 8mm deep socket. This is just a test prior to making my own, hopefully NON junk precision spinner tool.
