Manufactured from hardened and tempered chrome vanadium steel with shot blasted finish spare bits are available packed in impact resistant plastic case contents bit holder 10mm hexagon x 38 sq drive bit holder 10mm hexagon x 12 sq drive 7 x 30mm and 7 x 75mm draper tx star bits t20 t25 t30 t40 t45 t50 and t55 5 x 30mm and 5 x 75mm xzn spline bits 5 6 8 10 and 12mm 7 x 30mm and 7 x 75mm hexagonal bits 4 5 6 7 8 10 and 12