The combo includes 5 books
1. 151 essays -SC Gupta (For UPSC Mains) it's a little eaten by insects but over all the content is safe and sound

2. Arihant general knowledge book- a bit old but good content

3. general knowledge quiz book - has a range of questions

4. 501 fascinating facts- interesting facts and it's very new

5. Jokes book- jokes :)