Herm Sprenger Single Jointed Loose Ring Snaffle Bits are anatomically designed for a better fit in your horse"s mouth. Herm Sprenger from Germany is renowned for its outstanding quality and technologically advanced designs. The Sprenger seal of quality has guaranteed safety and precision workmanship for over 135 years! Herm Sprenger has developed two metals specifically for use in bits: Aurigan and Sensogan. Both are nickel-free alloys designed to taste better and promote salivation for a softer mouth. Aurigan is an alloy of 85% copper, 4% silicone and 11% zinc. The Aurigan metal has the mouth softening properties of a copper but is stronger due to the addition of silicone. Aurigan increases salivation to encourage chewing and swallowing which promote relaxation. Sensogan is an improvement on the Aurigan metal. It has a reduced copper content as well as added Manganese. The Manganese helps to regulate oxidation to release less copper for less salivation. This may be beneficial for horses who tend to salivate too much with the Aurigan mouthpiece. The slow oxidation also means that the metal will keep its white gold color longer. Herm Sprenger sometimes also offers German Silver (though it will be phased out, replaced by Sensogan) as a mouthpiece which is a highly polished metal containing approximately 60% copper, 12-16% nickel and 18-22% zinc. Metal: Aurigan with stainless steel rings, German Silver, or Aurigan with Aurigan rings, Sensogan with Stainless Steel and Sensogan with Aurigan Not all sizes and thicknesses are available for each metal Thickness: 14 mm, 16 mm, 18 mm or 20 mm Ring Size: 70 mm (2.75590")