1. Function of rubber grommets oval: Rubber seal could stop air, water, and dust enter the machine system, which could protect the machine or parts to be healthy and working well. 2. Features of rubber grommets for bongs: Excellent chemical and physical property, excellent oil, high/low temperature-resistant, wearing-resistant, oil-resistant, dust-resistant. 3. Application: Railcars,automobile,steamboat,industrial electrical equipment,building door& window,construction machinery,construction bridge and tunnel. Etc.