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Your just looking for a D/20tpi to ASR adapter.  Then you can use one of the ASR to 3 lugs like you posted (Silenco Co version looks lighter).  SPC and others sell them.

cool. i found 2. I wish there was more than .031" difference so it didnt have to be a long adapter, but such is the math.

Actually, 1.375-24 major and 1.4375-20 minor overlap.  If there were .031 difference between external Dmin and internal Dmaj, we could nest them.

Your other option is a D cell to B cell (1.180-24) or D cell to Alpha (1.125-28) adapter.  Gemtech,  Liberty and SDTA make B cell size 3 lugs, SiCo & Kaw Valley make Alpha pattern 3 lugs.

Pretty sure SDTA has a D to B adapter, not sure if anyone is doing a D to Alpha.  Our D cell boosters do take Alpha accessories,  but it's not just a simple adapter.

Not surprised they overlap. I didnt even bother checking the minor diameters. I did the math on the diameter difference. I ended up ordering an adapter from SDTA and the YHM.

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