Samuel Caster is an American businessman who founded Mannatech, a multi-level marketing firm located in Coppell, Texas.
[1] In the late 1980s, Caster founded Eagle Shield, which sold an insulation product that it claimed was based on new technology developed by NASA and that could reduce heating and cooling costs by up to 40%.
In May 1988, the Attorney General of Texas concluded that the product's technology long predated NASA and did not reduce consumers' bills in the amounts advertised.
The Electracat reportedly emitted pulsed vibrations that repelled rats, crickets, snakes, ticks, spiders, mosquitoes, and scorpions.
[3] In October 2007, it was reported that the company had fired Grant Thornton LLP as its auditor after the accounting firm demanded that Mannatech remove Caster from all responsibilities.