DURABLE: These durable 150mm bits are made from strong S2 grade steel with serrated non-slip tips. CONTENTS: The set includes the following bit heads: Pozi #1, #2 (x2), Phillips #1, #2 (x2), #3, Slotted 4mm, 5mm (x2). PLEASE NOTE: They are not suitable for use with impact drivers or wrenches.