The railless system facilitates the rapid mounting of framed PV modules on trapezoidal metal sheet roofs with minimum thickness 0.8mm, only four components are required to install the modules directly to the roof. A base mounting clip is 100mm or 140mm long, therefore easy to carry and attach to almost all trapezoidal and sandwich roofs. The EPDM sheet is in the package to seal the screw against the metal sheet. Railless mounting system allows for easy logistics, cost -e ective warehousing and easy mounting.