Reduce time and increase productivity on mice tail injections and tattooing! The only mouse restrainer in which the tail can be rotated. This feature provides for easy access to either vein in the tail for an i.v. injection. Animal chamber accommodates mice weighing up to 45g. RTI is ideal to adequately restrain an un-anesthetized animal while having the tail vein straight in line with user's eyes for a successful injection. A pattern of air holes provide ventilation as well as a "toe-hold" for the mice. The unit sits comfortably on a bench top or in a laminar flow hood and it can be U.V. sterilized for use with immune-compromised mice. The raised table top lets user rest their hands to administer the injection.