... Certification Ningbo Zhenhai Hualong Fasteners Co., Ltd. Manufacturer of bolts ,nuts,wcrews,washers and other fasteners.We often make the productions ... best you can trust. Looking forward to your cooperataionRegarding to Bolts StandardDIN931,DIN933,DIN6914,ASTM A325M,ASTMA325, ASTM A-10, ... can make accroding to your drawing or your sampleRegarding to Nuts Type of NutSquare,Hex,Flange,Hex socket,T-type, ...