The invention discloses a low profile input device for moving a cursor, scrolling a page, or selecting a function on a display of a handheld device. The polycylic fluoroalkanes are useful in a wide variety of applications, including optical couplants, optical cements, optical elements, optical inspection media for semiconductor wafers and devices, and immersion photolithography, particularly at 193 and 248 nm exposure wavelength. When a pad is in the retracted position, the body surface that would normally be occluded by the pad becomes accessible to spray from a nozzle so that the body surface can be cleaned. As well, the sheath introducers can also contain a stationary valve and housing that can be opened to expose a portion of the hub when a conduit penetrates the stationary valve.