I do a lot of woodturning, so eventually it was necessary for me to buy an air supplied shield. After hours of research I decided the Trend Airshield Pro was the best choice for me. It was expensive, but with some more research I found one online for less than $300. It works great. I'm really happy with it. After about a year the battery refused to hold a charge. No big deal--rechargeable batteries wear out, won't hold a charge and need to replaced occasionally. I went online to buy a new battery and was shocked at the price. They cost $70. I thought that was crazy. I took the battery out of the helmet and noticed that it was just a plastic container holding a battery pack. The battery pack is marked 3.6 volts, 3600 mah. I took the plastic container apart, which was really easy. It just snaps together. Inside was an unlabeled, shrink wrapped group of three batteries. I scoured the internet looking for a replacement but could find nothing. You can't buy a 3.6 volt, 3600 mah battery pack. It looks like Trend had this battery specially manufactured just for them, forcing you to pay three times what the battery should cost to keep your AirShield Pro running once the battery wore out. Things like this really piss me off. I have no problem with companies making money, but when they design products that require purchasers to continually pay for that product by forcing their customers to buy overpriced, proprietary consumables, I refuse to play that game. Had I known I would only get a year out of a $70 battery, I could only buy from Trend, I would have bought something else. Continue reading "Trend Airshield Pro: Build Your Own Battery"