In many countries, mainly banks provide bank guarantees. The big disadvantage of this is that banks will subtract this
from your bank credit. 
More and more insurers are involved in issuing surety bonds. Normally, they do not ask companies for guarantees, and they will not reduce your bank credit. In addition, the credit rating of many insurers is much better than that of banks.

There are several kinds of surety bonds:

Keystone Trade Credit and its partners work with several insurers with strong credit ratings to set up facilities for surety bonds