Dear Sir,
Due to the raw material cost of company increasing, we have to increase the price of below models for 5% base on the original price from now on：
Model ABCDE
Model EFGHI
This is a tough decision and we understand this will bring you inconvenience, but 5% is our best effort to keep balance between our customers and covering our cost.
We greatly regret any inconvenience it may cause, and hope we can receive strong support from your side.
Thank you very much. I'm available for any questions you may have.
Best regards