Head Magnetic DesignBlack Screwdriver Tip guarantee long service life, increased corrosion protection and accurate fit into fastener Excellent Material Insulated Screwdriver Set adopt Chrome Vanadium Steel Blade,stronger and more durable than standard steel, offer more strong torque and resilience to prevent stripping SafetyEach Insulated screwdriver tool is individually tested and Insulated to 1000 volts AC. Box Includes. Full size of 4 Slotted Insulated screwdriver - 3 x 75mm, 4.0 x 100mm, 5x125mm, 6x 150mm; 3 Phillips Insulated screwdriver - PH0 3 x 75mm, PH1 4x100mm, PH2 5.0x125mm; PH2 6.0x150mmVoltage Tester(100v-500v testing range) Widely UseThe magnetic tip insulated screwdrivers are suitable for electricians, building computers, and working with breakers or electronics, electrical fields