Clues :
1. I look best when I’m covered in stamps.
2. I contain lithium ion and I give life to the most-loved device on the planet.
3. I resemble the first letter of the fastest land mammal on earth and I have cushion stuffed in me.
4. I help you fall asleep in broad daylight.
5. I used to be known as “Schweizer Offiziersmesser”, but then the Americans changed my name.