Got my new bolt in today. Only took 3 days and free?! Once again impressed with Kel-Tec customer service. New RDB bolt on the right. New RDB extractor on the bottom. Notable differences: Different shape to the openings of the 'extractor axis pin' and 'ejector pin' on the bolt body. There is a small recess or shelf inside the 'extractor axis pin' hole on the extractor itself (see second photo, bottom extractor). There appears to be a different finish on the new bolt, extractor and even possibly the new pin. The pin itself is black like the rest (old was silver) and feels less slick compared to the old pin (possibly providing more friction). The diameter of the new 'extractor axis pin' is slightly smaller than the 'larger pin' originally intended to fix the pin walking issue (new pin 0.1015in vs old 'large pin' 0.1025in) NOTE: As an experiment I could not get the old 'larger' diameter pin to install fully into the new bolt. Did a simple "single finger push test," placing my extended index finger against the back of the punch placed against the axis pin, comparing the tension of my old axis pin (with larger pin and BCM upgraded extractor spring) and the new axis pin as delivered. While my old bolt's pin will walk after a fair amount of "single finger pushing," I was not able to get the new pin to walk at all using the same method. Completely non-scientific but I was impressed regardless as I felt I was applying a fair amount of force even if it was only my index finger. Can't wait to shoot it!