Nike Calm Mules In Black. A water repellent mule with a contoured foam design featuring the signature Nike Swoosh logo debossed on the outstep. A woven velcro fastening strap around the heel to hold the foot in place with a black foam heel guard featuring the signature Nike logo. A black textured footbed featuring the large signature Nike Swoosh logo and a black branded and grooved rubber undersole. Colour: black