SVG - Different stroke width on different svg items

The viewboxes of the two SVG are quite different...one is 7 times the size of the other.

So....to get the same effect you must use the same multiplier for px size (at least as an interim step pending other options)

JSfiddle

#A path {
  fill: none;
  stroke-width: 10;
  stroke: red;
}

#B path {
  fill: none;
  stroke-width: 70;
  stroke: red;
}

svg {
    width:128px;
    height:128px;
}

You may be able to see what else might have a similar effect with a little more research.

Useful Article/tutorial

EDIT: A quick google gave me this property:

 vector-effect:non-scaling-stroke;

Reference Link

JSfiddle Demo 2

path {
  fill: none;
  stroke-width: 1;
  stroke: red;
  vector-effect:non-scaling-stroke;
}