There are two types of screws, cruciform (+) and allen (0), it's a matter of taste, no difference in quality. There are several sizes of screws. 7/8: just the right size to screw the trucks onto the board. 1 ': long enough to put pads. 1'1 / 4: to put two sets of pads if you really have big wheels 1'1 / 2: this is really for big pad, see also longboard. In general, 1 'is used which are the most versatile screws.