T cell receptors (TCRs) having the property of binding to a murine insulin-derived peptide, LYLVCGERG (SEQ ID NO:62), presented by the murine H-2Kd complex (LYLVCGERG-H-2Kd). The TCRs comprise at least one TCR α chain variable domain and/or at least one TCR β chain variable domain and have a KD for the LYLVCGERG-H-2Kd complex of less than or equal to 1 μM and/or have an off-rate (koff) for the LYLVCGERG-H-2Kd complex of 0.5 S−1 or slower, and use of such TCRs as research tools.