Sinn watch 900 pilot s rubber black signifies objectivity and functionality both of which are inherent in the design of the 900 pilot s pilot watch but there is a further connection to the colour black the s in the model name stands for schwarz black signifying the black hard coating of the watch there is an overriding sinn priority behind this the suitability of each watch for everyday use to achieve this we have additionally hardened the satinised stainless steel case using tegim