This seems a quite well built machine , but I would not call it a shredder. It chews the sticks and branches up but does not shred them. The mechanism could be likened to a cog working against a backplate. When used it left the branches and sticks crushed but still in lengths with notches in them. I even put branches at 35mm in and it did the same. If you put green waste in it will do very little to them and would not do a great deal to assist composting as this is a consideration when buying this machine I sent it back as it did not shred which I wanted to make a mulch for my garden. I wish I had known how it worked and the results. My lawn mower does a better job of composting preparation of twigs and green waste. Obviously no branches!!