I have TPMS on all my tires including my trailer tires. I double check and adjust the tire pressures before I install the pressure sensors before each trip. If I get a pressure alarm I stop on the shoulder if a rapid pressure loss, or at the next exit if a slow pressure loss.
My Roadmaster tires are absolutely made in China. It says "Made in China" right on them. (I went out and looked to see what it said.) The brand name stamp says Roadmaster followed by "Engineered by Cooper Tires". Cooper treats Roadmaster as a separate brand even though they own the brand.
Ok... still would like to know the DOT code..