Electrical tool set: To ensure safety when working on live parts it is necessary that NO standard non-insulated ¼“ bits fit into the bit chuck. VDE tool set: electrician's tools: Each tool of the VDE nut driver insert set is individually tested at 10,000 V AC and approved for 1,000 V AC. Perfectly suited for electrical applications in the electrical sector. Bit set: Low-lying screws or difficult-to-access areas can be easily reached by the screwdrivers with an up to 33% slimmer screwdriver blade. Electrical tool set: Space saved thanks to extensive interchangeable bit system and nut driver inserts. Tool set with protective insulated blades and VDE test ensure highest safety for every type of electrical application up to 1,000 VAC. (Tested according to IEC 60900:2012).