The main important part of Static Gk in CLAT & AILET is Indian History, the basic knowledge of science & You should also know about the working of the government, its main agencies and parliament. You should also focus on current events.

You can prefer below given books.

General Knowledge by Arihant 

Lucent GK (Subjective)

Pratiyogita Darpan in Polity, Modern and Medieval History

Good Luck!