Classic Red Top™ magnesium is our standard and trusted photo engraving sheet made from the purist magnesium and cast and rolled in our Saint Louis USA facility. Red Top™ photo resist has been manufactured since the 1960’s with many iterations along the way as the ingredients within the product have become superseded or no longer available, however Red Top™ photoresist remains the choice of many due to its robust characteristics and ability to hold fine details during the etching process.