as the tooth are angled, they operate A lot quieter than the more cost-effective straight-Minimize steel gears. It took me some time to locate this tear-down pic verifying which the gears were helical. Pic courtesy of https://shaunalsby412091.techionblog.com/28945447/helping-the-others-realize-the-advantages-of-talaria-sting-r-mx4-range