Rieker Shoes (Trainers) - Available in women's sizes. by Rieker. Looking for something in-between? Somewhere between a flip-flop and a sandal, this model by Rieker does it all. As a brand that has a lot on its plate when it comes to trainers, it is taking advantage of this opportunity to bring together all the elements that have made it such a success. Do you dare try out this pair of trainers that defy the odds? The best thing is for you to judge for yourself! Available sizes: 3.5,4,5,6,6.5,7.5.