I asked Dan at River Country what is the accuracy rage of the RC T34 example +/- 1 degree, and are they ASME 40 Grade A tested?
His answer was "The accuracy rate is 99.1% full scale. We do a 5 step dry heat cycle testing across the range of the dial, so unlike other models that say +/- 5 degrees at 200 but then at 400 the difference is doubled ours at 99.1% at 100 or at 500 degrees. Our thermometers are not officially tested at specific test as you asked, we use a thick 304 stainless housing and then we use 316 stainless on the welded stem so it last longer in the cooking chamber".
I bought one.