Okay thats great, can you please quote me for 100 units 4140 steel of my round head bolt, Nickle plated ? Steel needs to be heat treated as follows. --- Heat to 840 C - 875 C, hold until temperature is uniform throughout the section, soak for 10 to 15 minutes per 25 mm section, and quench in oil, water, or polymer as required.Few more questions as follows. Does your company have capacity to heat treat in this method, as outlined above ?Do you have any photos of nickel plated 4140 bolts you have done ?Do you have test results of 4140 heat treated bolts strength ? Thank you for your time in replying , Next week i would like to arrange a Skype meeting if possible so i can tell you about my company in person and the projects.