Patent ID: 7011794

Claim:
An improved cartridge with a body of non-magnetic inert material adapted to be slidably engaged in a receptacle of an apparatus for performing optical analysis of a fluid sample, said body having a domed cross section with an optically clear flat land portion adapted to be positioned in a field of observation for optical analysis, a test chamber underlying said flat land portion adapted to be filled vertically along a longitudinal axis with said fluid sample, a vestibule above said test chamber adapted to act as an overflow reservoir capable of being sealed both from said test chamber and an exterior environment, and an inlet between said test chamber and said vestibule, wherein the improvement comprises: a. a handle portion flanked by a grip area made to flare along a longitudinal axis of said cartridge outwardly from said handle; b. said handle having an arch-like extension on a stopper face, said stopper face located orthogonal to a first face whereby said first face is located on said domed side of said body, said arch-like extension spans between said grip area; and c. a second face having an inner framed structure bounded along a radial axis by two keeper elements and along a longitudinal axis by said stopper face and by an enlarged mouth of said vestibule, said second face located opposite said first face of said body.