product dropping big problem

... think like this diagram
+-----------------------+
| product in the air |
+-----------------------+
|
|
v
+-----------------------+
| product on the floor |
+-----------------------+
|
|
v
+-----------------------+
| product broken |
+-----------------------+
think this way...
product dropping, so many problem...
1. product's age (経年劣化)

2. installation method (取り付け方の誤り)
so... company say: "please follow safe installation method"
and also say: "if product is old... stop using it"
