Old Gringo - Reno Mule (Black Calf) - Women's: Stylish western mule from Old Gringo(R). Goat leather upper. Detailed embroidered design. Leather lined. Leather outsoles and heel. Tip of heel has added rubber for slip-resistance. Old Gringo(R) boots go through a 130 step handmade production process. Old Gringo(R) also develops and tans its own leathers and textures to make sure the end result is a superior quality product.