Since I couldn't get an exact Original Equipment match for my IRC 130/90-16 tube, I called D.K. and they confirmed this would work for my 2001 Suzuki Intruder Volusia 800. It has the 90 degree valve stem like the O.E.
Black plastic valve cap. (I used my old metal valve cap)
I used this tube with the O.E. front tire: IRC GS-23, 130/90H-16, part # 541355.
Valve stem lock nut is NOT attached. I almost missed it when it fell out as I unpacked this tube. Note that tube should have convex washer, then nut for inside and then the loose nut for outside the rim.
Also replace rim strip at the same time with part # 535197.