The Shure SFG2 was a stainless balance with mirrors - found out late on it was slightly magnetic - not very good with MC!
Why? Apart from sticking to the cart a bit as you lift off, it will be entirely accurate, or as far as it could be anyway. The balance is measuring down-force ONLY. If the base was magnetic, fair enough, it would be rubbish, but the base is plastic.
An apology to various here - it IS a Shure here - just dragged it out - Shure SFG-2 Stylus Tracking Force Gauge (basevinyl.com)
90% certain it is Hunt EDA but as I say I can't find a link to it on google.
Is that not a carbon fibre brush?