| 摘要 |
A knapsack is made of a hard thermoplastic material and is molded into a single-piece construction. The knapsack has a rear wall surface facing toward a user's back and formed with a plurality of spacers to result in a spacing between the rear wall surface and the user's back. As a result, the knapsack does not attach closely to the user's back and, therefore, permits air ventilation and can provide a massaging effect.
|
