All nipples are made of food grade, heat-resistant liquid silicone, which is Nitrosamine-free, non-sticky, odorless, safe and conformed to the FDA.是什么意思_All nipples are made of food grade, heat-resistant liquid silicone, which is Nitrosamine-free, non-sticky, odorless, safe and conformed to the FDA.在线翻译_英语_读音_用法_例句