Abstract: Disclosed are adaptor devices configured for attaching an indicator, such as a light source, to an infusion line to aid a user in identifying the infusion line, matching different sections of an infusion line as belonging to the same infusion line, distinguishing the infusion line from other infusion lines, and/or sensing of various parameters of the medical line. The adaptor device includes a receiving surface and one or more sets of laterally opposing grip elements projecting from the receiving surface. The grip elements are configured to accommodate medical lines of variable size.