A desktop type batch reverse jig and prototype bench scale continuous reverse jig were designed by installing a top screen to the chamber of the RETAC jig. Shredded plastics of polypropylene (specific density 0.91) and high density polyethylene (specific density 0.96) were used for the tests and operating conditions were investigated using a desktop type batch jig. Waveform and screen design affected the separation results. Wettability control of feed sample is also important and 100% separation was achieved for the top and bottom layer products. The prototype bench scale continuous jig could obtain a high grade product, 99% pure as a bottom product. (C) 2010 Elsevier B.V. All rights reserved.