backpack and hard case sleeve for P70

I bought a P70 recently and I am now looking for a backpack that could fit it and multiple textbooks. I carry 4 textbooks with me and some other documents. I am literally looking for the biggest and most durable laptop backpack.

Also, has anyone ever found a laptop hard sleeve case like this one
http://www.pelican.com/us/en/product/watertight-protector-hard-cases/hardback-case/laptop-case/1095/

but for large laptops like the P70?

 

I can recommend you two laptop backpack for your P70
https://www.amazon.com/dp/B01N76FWCM 13.4”(L) x 18.3”(H) x 4.5”(W)
or
https://www.amazon.com/dp/B01M5LLICK 12.2”(L) x 17.8”(H) x 5.5”(W)

 

here is my review of the everki titan last year. I can fit my dell 7710 in it very easily (which is probably near same size as your Lenovo P70) along with all of my gear. I like it alot

http://forum.notebookreview.com/threads/hands-on-dell-precision-7710.785166/page-58#post-10265700

http://forum.notebookreview.com/threads/hands-on-dell-precision-7710.785166/page-58#post-10265729

Everki makes a Titan with wheels now too but I've not seen it in person.