Twistheads are a brand of key chains/toys produced and included mostly in Kinder Surprise - European consumer product which includes toys hidden in a chocolate egg. Kinder Surprises are not available in the United States due to US law regulations regarding hiding inedible objects in edible products.
A series of Twistheads based on TMNT 2012 series were copyrighted and released in 2014.
Each Twisthead figure is a highly stylized small figurine with round head which could be opened to reveal a special mechanism, which could be used additionally for simple cypher-based games.
No special sculpts were made for series and the only exclusive part of TMNT series is the paint job.