Kenner employed a number of different urethanes during the 80's. Sometimes new materials were tested to see how well they worked. Dynacast, a green urethane, represents the most common material used in the creation of Super Powers hardcopies. Not long ago, a legitimate Manbat hardcopy was temporarily and secretly taken from a reputable dealer. The individual made a mold from this authentic hardcopy and produced white resin copies of the figure and proceeded to pass them off as authentic hardcopies. These particular copies are indeed fakes.
Given that information, one might view the issue as clear cut: white equals fake, green equals legit. Unfortunately the issue is not so simplistic. A number of legitimate green Manbat hardcopies surfaced from an ex-Kenner employee. This batch also yielded white urethane parts. There were enough white parts to piece together 3 complete, white hardcopies. I've seen two 100% legitimate Star Wars painted hardcopies from the Droids line cast in a white urethane. The timeframe of that series coincides fairly well with the timeframe of the unproduced 4th series Super Powers figures. Given that information, it appears these 3 white urethane hardcopies are legitimate.
When presented with the opportunity to buy a Manbat hardcopy, which doesn't happen often, collectors need to use sound judgement. I hope the information provided here will assist collectors and help them avoid purchasing a fradulent prototype. A green dynacast hardcopy is a very safe bet. If the piece is cast in white, I recommend being extremely careful. One of the three white Manbats that surfaced with the green ones is locked in a personal collection and not likely to hit the market. I am unsure of the whereabouts of the other two at this time. The exact number of white resin copies is also unknown, but I am fairly sure it exceeded 10. Therefore, the chances of a white Manbat hardcopy being a fake is extremely high. As with the purchase of any prototype, knowing its source and buying from a reputable seller is of the utmost importance. It is a small hobby and many collectors, myself included, are dedicated to dispersing the most accurate information possible. If anyone has a question about a Manbat or any other Super Powers prototype they are considering buying but have questions about, please feel free to drop me an email at: firstname.lastname@example.org and I will do my best to help.