Blood Bag Shaker MR 921 is compact instrument to provide smooth and gentle rocking. The blood collection monitor provides homogeneous mixing with anticoagulant but without the clot formation of blood cells during collection of blood from a donor. Preset standard volume is easy to change in blood collection monitor. Provision of pausing collection and change set volume during pause is also provided in blood collection mixer. Hi-Tech Instruments has provided its blood collection monitor with .This blood collection monitor also has audible alarm.