(1) 45# steel quenched and tempered
(2) 60Si2MnA High strength spring steel
(3) Number o f turns is enough
(4) Roughness as well as original material
(5) Produce according to the export standards
(6) Precision casting
(7) Rolling and optical processing inside
(8) Gloss is strong
(9) 40 hascrome
(10) Using high precision mirror polishing
(11) Precision casting, high strength and abrasion resistant