The Nippes 37sr and 9sr tweezers we carry are hand ground, making them unique as everybody else uses computerized machining. You can feel the craftsmanship of a small family owned company even in something the Germans put to market for under ten bucks. Mildly ‘frosted’, textured gripping zone. For some reason they’re officially “SR”, both, yet only have the # and an “R” embossed upon ’em; go figure the Germans and all their numbers. Maybe the ess is always implied.
I believe the “R” denotes that these are the INOX Rostfrei stainless steel versions. In this country (USA), everybody wants stainless steel. That’s what sells. You’re a fool to stock anything that’s nickel plated carbon steel, and it doesn’t matter how good the product is (even when it is a little better than the stainless versions because of the metallurgical advantages afforded to carbon steel) or even if the buyer lived in Nevada (where it’d never matter anyways) or has a nickel sensitivity (stainless steel tools have more nickel than carbon steel tools even with their nickel plate, and if you use it daily and are in that small minority represented to me by a knowledgeable German producer as 0.5% you’ll get redness on your fingertips from using stainless steel things regularly, like if you’re a hairstylist or nail technician). So, when there is two versions of the same tool and only the metallurgical formula changes, we’ll only buy the stainless ones to sell to you, and in the rare cases where a singularly unique item’s offered only in carbon steel we’ll just buy that, obviously.
Stainless steel does have one other meaningful advantage; it can be subjected to steam-sterilization (important in a professional setting like a nail salon but of no consequence for home use).