Sybian wired remote control. Flexible moulded attachments are supplied which fit over the vibrating ridge and shaft which mostly have integrated dildos on their top. In use, the rider locates the dildo into their body cavity for internal stimulation while pressing their external erogenous parts on the vibrating ridge. According to its inventor Dave Lampert, the Sybian was first conceived in the 1970s, and developed in 1983. A prototype was built in 1985 from sheet metal mounted on a wooden frame with a vibrator projecting through an opening inside the housing; a second prototype became the basis for current production models.
Is-a function g just works for Rectangle class but not for Square, and so the open-closed principle has been violated. Is-a In knowledge representation, object-oriented programming and design (see object-oriented program architecture), is-a (is_a or is a) is a subsumption relationship between abstractions (e.g. types, classes), wherein one class "A" is a subclass of another class "B" (and so "B" is a superclass of "A"). In other words, type A is a subtype of type B when A’s specification implies B’s specification. That is, any object (or class) that satisfies A’s specification also satisfies B’s specification, because B’s specification is weaker.