The Key of Z Rubboards Womens Pro/Custom Washboard: Handcrafted out of 24 gauge Stainless Steel. Unlike the Standard Womens Washboard, The Pro/Custom Model Comes with Dimples on the Top and Bottom of the Washboard, they are a very nice look especially on stage under the lights. Bottle Openers and Signed Product Card Provided. This Washboard was first designed for Pop Artist Rihanna.