This web site, which is nearly all in Chinese, dispalys the extensive 2017 range of LTWOO transmission products. For mountain bikes it covers 'one by', 'two by' and 'three by' systems with 8, 9, 10 or 11 rear sprockets, with maximum sprocket sizes up to 42 teeth. It also includes straight bar road bikes and that peculiarly Chinese category of folding bikes. Coloured three speed derailleurs for folding bikes seem to be hot in China!
Image 21 gives a tiny amount of company history.