How to get china visa with an invitation letter

Hi, what type do you want to apply or what is your purpose for going to China?

I want to have visitor type and also want to buy a pasta machin from that company the one send me this invitation letter

If so, you can apply for a M type, which you can purchase by holding it. You can also travel in China with your M type

Dears
can you tell me if I submit my invitation letter to the china embassy how long will it take to get visa and tell me only the letter and pasport is enough to submit it or anything els. if you need for round air ticket and hotel booking how I can undrestand the fix date of the visa to have it.

The following are all the required documents for M type:
1. original invitation letter from any duly authorized Chinese unit or entity
2. original business license and its copy
3. the resident proof and its translation version
4. bank account with at least 4000 USD inside
5. original non-criminal record certified by Ministry of Foreign Affairs of Afghanistan
6. round trip air tickets

If you have been to China in recent five years, you just need to provide the invitation letter from duly authorized Chinese entity or unit.