This shoe was formerly called "Alpro S410". The size specifications in the selection field: "R" stands for "Regular" = "normal size", while "S" for "small" = "narrow width" is. I have worn this shoe even as Alpro, and am very satisfied. The foamed sole is much more convenient as the corresponding cork sole. With cork soles goes with me always the right heel broken, probably by's motoring. Keeps the foamed sole. And the latex heel pad is still elastic after years. I have the Alpro ordered on 25.04.2011. Today is the 12.17.2014. So I have the shoes worn for 4 years, from spring to autumn, at work, on vacation, because he is always and everywhere so comfortable. After 4 years is now the profile a little bit worn. Therefore, I take the shoe just as office shoes for the winter, and to order it to me again - as Birkenstock Kano. Without heel strap is available as a Birkenstock Bilbao, formerly Alpro P250.