Deck sizes on PISO skateboards are available in 7.75’’, 8”, 8.125”, 8.25” & 8.5''. Where say size 7.75in says the width of the board is 7.75in. A very general rule is that if you have big feet you might want to go with a wider board. If you’re smaller than UK size 8 or are shorter than 5’10” then a size 7.75’’ or 8” board should be good. If you are tall and have huge feet - go for an 8.25+” buddy