Awesome, I have a new Dr.D exhaust system for Dyno tests. Dubach racing has developed a pipe for the 150 and I am testing one to give the company some useful data and information. The pipe is clearly one of the finest constructed pipes I have ever seen for these bikes (like all of Dr.D pipes) The entire exhaust is made from stainless steel, and the muffler is a "D" shape and is made from aluminum. I will be testing shortly on a stock CRF150 and 230. I've been informed that Dr.D may also be manufacturing a separate exhaust for the 230, but I am going to test this one on a 230 also for comparative data purposes. Look for Dr.D CRF150 exhaust to be available now or very soon!! It is definitely an awesome pipe!!