class SkateHelmet_ColorBase extends HelmetBase
{
}

class SkateHelmet_Black extends SkateHelmet_ColorBase {};
class SkateHelmet_Blue extends SkateHelmet_ColorBase {};
class SkateHelmet_Gray extends SkateHelmet_ColorBase {};
class SkateHelmet_Green extends SkateHelmet_ColorBase {};
class SkateHelmet_Red extends SkateHelmet_ColorBase {};