Plastic crusher/Plastic shredder is mainly used for meeting large capacity requirment and for crushing hard plastic like lump. If your material is in bale you don't need to unpack them, what you should do is just put the bale into it, of course this shredder is twin shaft strong crushing machine.
There are two kinds of shredders: Single shaft shredder and double shafts shredder.

 We can suggest you which one is the best for you according to your material.