No clue why you ask, but Autolite 308, NGK BR2LM, Bosch WR9EC, Briggs # 802592s, Tecumseh 35395
an eqivalent ratio is an ratio that is equal or you can simplfiy it
Equivalent
Rj19lm
Champion spark plug RJ19LM is for lawn mowers or similar equipment. The standard gap is .030 inches or 0.76mm.
Resistor
Rj19lm
yes
If you damaged a Champion RJ19HX spark plug, then you can indeed replace and substitute that with a Champion RJ19LM spark plug due to the similarity in their sizes.
NGK Insulators's population is 3,272.
ngk BPMR4A
0.648 = 64.8%