Abstract: A receptacle includes a main body and first and second covers. The main body includes a bottom wall, and a surrounding wall extending upward from a periphery of the bottom wall and having a substantially flat top annular face on a top periphery thereof. The first cover covers tightly the main body, and includes a first cover portion abutting fittingly against the top annular face of the surrounding wall, and a first peripheral portion surrounding the top periphery of the surrounding wall. The second cover includes a second cover portion covering the first cover portion, a second peripheral portion surrounding the first peripheral portion, and an annular pressing shoulder formed between the second cover portion and the second peripheral portion to press the first cover against the top annular face of the surrounding wall.