Possible Clues:

• Hiker's load
• (Hiker's) backpack
• Beat up with A signal on your back
• Bag carried over the shoulder
• Hiking aid
• Bag requiring special technique -- pa's confused packing it
• Hitchhiker's load
• To sleep, say, on bed, one may lie on one's back
• Walker may use this trick to take in silly sap
• Odd bits of pasta popped into gift bag