[MW:31166] API 6A MONOGRAMMED COMPONENTS MATERIAL CLASS INTERCHANGEABILITY

Dear Experts,

Good day to you all!

I have a concern, where the material class of API 6A product scenario is as per below table,

Can I accept the if the Manufacturer gives a higher/lower class for Main/Sub level components against PO requirement?

I m very well aware that Client may say it must be as per PO requirements, and some clients may accept if they get a higher class product is given for the same price. But I d like to know what does API say about this?

Please explain what all can be done in this kind of situations.

thanks and regards

raj