The climate in the mountainous areas has changed. The previous minute was still cloudless. The next second was turbulent and it started to rain. Even if you read the weather forecast, it would be good weather, but you cannot guarantee that it will not rain. The backpack of ALICE is just like life. It contains clothing, food, shelter and related items needed in the mountains. If it gets wet, it will affect the lives of the people. When the clothing on the body has been wet with rain, if the sleeping bag, Replace the clothes and so on are also wet, wear wet clothes, plus the water bag is also wet, then it really waits to be frozen in the cold at night! 1. It's true that there is a large plastic bag, which is the kind of large plastic bag that was previously used for garbage. When preparing items, you can put large plastic bags into your backpack and start loading the clothes, food, and equipment you want to carry. The cheapest is a big roll of big garbage bags. The disadvantage is that they are thin. It is easy to break, and there is a thick transparent plastic bag, which is more durable, but the weight will be heavier than the big garbage bag. 2. Even if the backpack cover is equipped with a large plastic bag, it does not mean that we can rest assured that, in general, the material of the large backpack is not waterproof, so in addition to the backpack inside with a large plastic bag to ensure a layer, of course, the backpack must cover On the backpack cover, and on the mountain you will see many people use backpacks to cover the backpack even if it is not raining. Why? Put on a backpack to protect the backpack, it can also block the dew on the plants to wet the backpack. 4. Waterproof bag Ordinary plastic bag is easy to break, and the sealing area is still possible to enter the water. If it is really wet, things in the plastic bag will still be wet, and the waterproof bag sold in the market will have better waterproof effect. Consider using a waterproof bag to hold items such as sleeping bags. 5. When using waterproof clothing for hiking, most of them will carry clothing with waterproof function. If they are not worn, they can be placed on the top of the backpack or on the outside of the backpack to protect other items in the backpack. They can also use these waterproof clothing. Pack other equipment or food. Although there are backpack covers outside the backpack and there are large plastic bags in the backpack, it is never too much to strengthen waterproof measures! Water Drawing Board Guangdong Jishengke Industrial Co.,Ltd , https://www.jskpad.com
Therefore, even if the departure is a sunny day, the backpack is best to do waterproof measures, the following will provide you with a few good things. 
Because many people prefer to make the backpack cover worn, scraped, and do not want expensive backpacks to be worn or scratched, simple, thin backpack covers are not expensive, and some are thicker and more wear-resistant. The backpack cover made of the material, of course, the price is much more expensive. 
3 plastic bags or clip chain bags in addition to inside and outside the backpack to ensure that the waterproof, the backpack inside the clothing, food, data and other things afraid of moisture, but also the best use of plastic bags or clip chain bag installed, the opening all sealed In particular, sleeping bags, spare clothes, and down jackets must not get wet, and even two layers can be placed just in case.
You may feel this way, but if you really have experienced how hard it is to get wet, you will understand why this is done. 
There is also a waterproof bag backpack on the market, although the waterproof effect is almost 100%, but the weight is not light! 