We recommend having three bags for your trip.
- a suitcase or large travel bag to check. Inside this, you can roll up your 90-liter duffel bag during your flight.
- a 35-liter daypack to use as a carry on and as your day pack on the mountain.
- a 90-liter duffel bag for items you’ll need at camp. The porters will carry this inside a large water resistant bag.
Read more here: http://peakplanet.com/how-should-i-pack-for-kilimanjaro/