Some of mine friend who playing the model aeroplane together, and always asked me, If I need buy a lipo bag for mine battery or not? I told, I Even use it for my cellphone charging, Hope it looking not so exaggerate; I saw many accident as some one charging and playing cellphone,  over charging and unstable elements,  makes the horriable accident,  the safety hazard may anywhere and anytime. I think there is nothing more valuable than our safety and health.  Do not wait until you lost and regret it. So it is necessary to make certain financial investment as to avoid life hazard.   The said investment is effective and sustainable and will grant you worthwhile profit in return.. Than how can we get a good quality lipo bag? It is our questions. Since we can see failure test viedo on youtu.be,  It maks us so confused and do not know how to make our correct choise.  Well,  we may know watching the correct one. There is commonly two kinds of style in market, first generation and second generation. see the pic. 1> first generation Charater: 1,the outside it is smooth, printed on logo 2, only inside part is fireproof materials. 3,Out side part is not fireproof. As the fireproof rating is not enough, that make its still get fire when the battery explosing. > Second generation ( this is upgrade one) 1, Clear weaven grain out side and inside also. Which is made of a kind of double-layer fiberglass. 2, The logo is embroided on 3,  It is much thicker than the first generation one. Then, lets see a video on youtube for more details. Lastly, For more intuitive understanding more difference  between first generation and second generation Lipo battery bag. Let's see below; 1> first generation fire-proof bag https://www.amazon.com/YND-Fireproof-Explosionproof-Protection-functions/dp/B06W5XZVH4/ref=sr_1_14?s=toys-and-games&ie=UTF8&qid=1492424425&sr=1-14&keywords=YND+lipo+bag 2>second generation fire-proof bag https://www.amazon.com/YND-Fireproof-Explosion-proof-Protection-180230mm/dp/B06WVLV8L2/ref=sr_1_7?s=toys-and-games&ie=UTF8&qid=1492424425&sr=1-7&keywords=YND+lipo+bag

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