A coalition of more than 200 footwear companies sent a letter to President Donald Trump on Wednesday urging him to walk back his newly planned tariffs on consumer goods imported from China.

The import fees will have negative consequences on the American footwear business and its consumers, wrote the letter’s 209 signatories, which include Nike, Adidas, Converse and Birkenstock USA.

“Although tariffs on some products from China will be delayed until December, the majority of footwear product lines face an added 15 percent tariff on September 1st,” they wrote.

“The highest tariff rates generally fall on lower value shoes and children’s shoes, driving up costs for hardworking American families,” they noted. “There is no doubt that tariffs act as hidden taxes paid by American individuals and families.”

Noticeably missing from the list of companies was New Balance, whose owner and chairman Jim Davis has donated around $400,000 to Trump. The company has spoken out against the tariffs on other occasions, however.

The letter was also sent to Treasury Secretary Steven Mnuchin and other Trump administration officials involved in the trade war.

“We are very concerned that this tariff action will create further economic uncertainty,” the letter continued. “An economic downturn will take away disposable income from U.S. consumers, even as they have to pay more for products. When consumers have less money to spend, we sell fewer shoes and this hurts U.S. businesses.”

Read the full letter here.