Autojack's professional quality metric 13 piece impact socket set is manufactured from chrome vanadium steel, electrophoretically treated for Premium Quality strength and completed with a polished black phosphate finish providing up to two times the corrosion resistance of traditional socket sets! Supplied complete in a strong blow molded carry case for safe keeping, each socket has its own clearly marked and precise location within the case for better organisation and quicker selection. Backed with a lifetime guarantee against manufacturing defects*.