The Sirius L is a compact high performance tube luminometer with unique features: The sample versatility is unmatched. The Quickstart capabilities provide results on the fly. The Sirius L detects less than 0.5 zmol of firefly luciferase. Light collection is maximized through both the proximity of the sample to the detector and the use of optimized light reflectors surrounding the sample vial. Closing of the sample drawer automatically initiates the measurement with no need to press any key. The sample chamber is designed for performance and flexibility. The instrument is available with up to two syringe-type automatic reagent injectors.