1,It use big roller instead of three smaller ones,so the ... can be adustable 3,V groove Purpose And PerformanceGrooving Machine for cardboard slot1,Environmental protection, no noise and ... :The groove is very smoothly.3,Convenience:this machine is very easy operation, you can put in ... no need using cleaner and air compressor machine. Parameter of the groove machine Type LS-1200A Number of slots(most ...