3 991 617 one such mechanism is depicted in fig8 and 9 which show a push button mechanism mounted in a meter of the type shown in fig3 the elements of the mechanism include shaft 44 which joins ejector 46 and push button 48 push button 48 works through shaft 44 to cause ejector 46 to disengage disposable 10 from the distal section 32 of meter 30 spring 50 works to return the ejector 46 and push button 48 to their retracted position push button ejection by permitting the disposable to be removed without direct contact helps to avoid contamination disposables to be used with push button ejection mechanisms of the type shown in fig8 and 9 preferably have a flange 19 fig1 depicts an embodiment of a meter of this invention which includes a display 50 for depicting the analyte concentration measured by the meter the display can be a light emitting diode led display a liquid crystal display lcd or similar display well known in the art although the above description and figs contemplate a disposable having a circular cross section and meter having a distal section having a mating cross section that geometry is not essential and in fact may not even be preferred a primary consideration in selecting the geometry in a photometric system is the optical design generally reflectometry dictates at least a minimum angular separation typically 45 u00b0 between a.