ALEXANDRIA, Va., Aug. 12 -- United States Patent no. 12,383,433, issued on Aug. 12, was assigned to Mengbaolong Technology Co. Ltd. (Hong Kong).
"Filter and noise-reducing earplug" was invented by Huobao Hong (Hong Kong).
According to the abstract* released by the U.S. Patent & Trademark Office: "Disclosed are a filter and a noise-reducing earplug, the noise-reducing earplug includes a filter, and the filter includes a shell, a flexible sound filtering block, and an adjustment pressing plate, wherein the shell is provided with a mounting recess and a sound outlet hole communicating with the mounting recess, the adjustment pressing plate is mounted in the mounting recess and forms a compression cavity with the mounting recess, the adjustme...