This allows the advantage of using more space than with the case of railed systems which require long distances to place a string of panels. Also compact design saves lots of tranportation cost as no need long piece rail.

This is the typical roof installation nowadays. Solar panels are attached to a single straight line of rails which are fastened to the rooftop through a set of roof-mounted assemblies, bolts and screws. Solar mounting accessories inlcude L foot, solar pv tile roof hook, hanger bolt , standing seam roof clamp, aluminum rail,mid clamp,end clamp,etc.