Monel (aka Nickel Bronze) has built in natural resistance to tarnish and corrosion yet it feels great to the touch and has it's own unique tonal color. This set has a round Core and gauges are 11-15-22-30-42-52. This gauging is becoming known as the "easy tension" set. Here's a video showing the tonal differences between some of the alloys that we offer including Monel.