I washed it before using it, but I was refused when I tried to use it, so no snot has entered it even once. I've washed it again and disinfected it just in case. There is a box and instructions, but the box may be flattened for shipping. Special structure to prevent snot from flowing back. - Brand: CHINAVI - Product Name: Handheld Suction Tank - Features: Easy to use with silicone tip - Structure: Special structure that prevents snot from flowing into the suction tube - How to Use: Easy to attach - Ranking: No. 1 in the Health Care category Thank you for viewing.