Use with either a spanner or socket. 
Special short length for use in a restricted space. 
Hammer this tool into damaged screw and reverse to remove the screw. 
Size: 3,4,5, 5.5, 6, 8, 10, 11, 12, 14mm & 1/8", 3/16", 1/4", 3/8", 1/2".