The ITL 6 Piece Insulated T-Handle Hex Key Set. Manufactured from injection moulded nylon thermoplastic, and the tools are 100% tested to IEC60900, Category C and ASTMF1505. They are designed to withstand extreme impact, abrasion, and are flame retardant. ITL tools are 100% tested using 1000 volts for 3 minutes submerged in water. They are Category C Impact Tested for operation within a greater temperature range -40F to 158F, -40C to 70C. Lifetime guarantee on both the tool and insulation. Supplied in a tool roll, contains: 6 x T-Handle Hex Keys: 3mm, 4mm, 5mm, 6mm, 8mm and 10mm.