Yes and no. The filters in the 2 and 3 are the same. The D1 is different. The 2 and 3 do not have all the o rings the D1 requires. Basically the HP seats are the same as are the diaphragms and diaphragm washers in the D1 and D2. The D3 uses a smaller diaphragm and washer. The balance chamber o ring is the same. Port plug o rings yes. It's the rest of the kit where the differences are. Best to use the right kit for the reg. When people start trying to mix them is when we see problems. And why would anyone want to buy the more expensive kit when it's not needed in the D1 and D2? As an instructor for the course I would never recommend one try to use a kit for a reg it's not designed for.
---------- Post added November 29th, 2014 at 12:00 PM ----------
Need to issue a correction on the D3. Just talked to Jack at HOG and because I have not tried to mix kits, which you should not anyway, the diaphragms and diaphragm washers for the D1 and D2 are the same. The D3 is actually smaller than both of them and therefore cannot be used. I wanted to get that out there ASAP and will be adding a note in the D3 service procedures and passing that on to Jack so it can be distributed to instructors for the course.
Sorry for any confusion. What it comes down to is as what I said earlier. Use the kit made for the reg you are using.
This is what I was trying to confirm. Apparently my understanding of the compatibility was incorrect (thought I had read that somewhere in another thread).
thanx