My main question here on this 410 concrete saw is this a strato carb for one of those stratified engines?? I am a little behind the times on some of this newer stuff because I have only done some reading and seen a few pictures on these engines and carbs . This is my first hands on experience with this type of carb that came in where I work part -time It started out with just a bad purge bulb that led to a total carb swap. My boss couldn't answer the question for me because he hadn't been to Stihl school for over 10 years . He also told me he isn't up on any of this M tronic stuff either even though they sell saws that are equip with it. Bear with me here , if I have this wrong please let me know. Pic 1 is a pic of the carb when viewed from the front or what I would call the airbox / air filter side . Bottom brass barbed fuel line goes to gas tank . The top two brass lines are for the purge /primer lines going to the remote plastic bulb . Choke plate at bottom with those three holes for the torx bolts to mate airbox to carb to intake manifold boot . I know a concrete saw is a different kind of animal than a chainsaw but would a chainsaw have a some what similar kind of mounting if it had this type of carb??? Pic 2 is just a view of the lever set up linking those two intake ports. Pic 3 is a view of the intake manifold side or boot showing the pulse hole and how the carb would look at idle with both throttle plates in the closed position. Pic 4 is a view of both ports in WOT with both throttle plates in the open position. The upper port is where that charge of raw air enters the cylinder in a strato engine during the compression part of the cycle . Do I have this part right or not ??? Like I said I am behind the times on this . Pic 4 is a view we have all seen before with the carb adjustments for the carb. This is a first for me which is why I am posting this just to satisfy my curiousity or is this just some kind of fancy carb only for a concrete saw. Just a side note , I have worked on what I would call kind of complicated chainsaws but they seem simple compared to a concrete saw . They mean business almost to the point of being over engineered but considering the work environment a concrete saw has to survive in I can see why they are built the way they are .