Cupping device, system, and features

A suction cup configured for use in cupping therapy, the suction cup comprising:

• a body comprising:
• at least one sidewall having opposite outer and inner surfaces and extending at least partially around an interior space, wherein the outer surface of the at least one sidewall defines at least a portion of an exterior surface of the body, the inner surface of the at least one sidewall is positioned between the exterior surface of the body and the interior space, and the inner surface defines at least a portion of an interior surface of the body that is contiguous with the interior space,
• opposite end portions at least partially defined by the at least one sidewall and comprising an open end-portion and a closed end-portion, the open end-portion comprising at least one rim extending around an opening to the interior space, and
• an intermediate portion at least partially defined by the at least one sidewall, wherein the intermediate portion is positioned between the opposite end portions and spaced apart from the rim;
• at least a portion of the body being elastic and configured so that the body is:
• capable of being squeezed to transition the body from an at-rest configuration to a partially-collapsed configuration, and
• elastically biased toward the at-rest configuration;
• a volume of the interior space being greater in the at-rest configuration than in the partially-collapsed configuration;
• each of the rim and the closed end-portion being less stiff than the intermediate portion;
• the intermediate portion comprising an overlayer adjacent an underlayer;
• the overlayer extending at least partially around the interior space and defining at least a portion of the exterior surface of the body;
• the underlayer comprising a polymeric elastomer and extending at least partially around the interior space and defining at least a portion of the interior surface of the intermediate portion of the body that is contiguous with the interior space;
• all of the underlayer is spaced apart from the rim extending around the opening to the interior space;
• and
• at least some material of the overlayer and/or the underlayer that is spaced apart from the rim having a higher modulus of elasticity than material of the rim and material of the closed end-portion of the body.