First contact the manufacturer to find out their interest and procedures for handling such things. Typically, if you don’t work for them or one of their ordinary designers, they do NOT want to hear from you, let alone receive a copy of your design.

In many cases, any unsolicited mail is read by a person outside of the company and returned to sender (or destroyed) before anyone from the company ever sees it. This protects the company from being charged with copying something they didn’t get from you but independently came up with something similar.