This is a 60mL Child Resistant and Tamper Evident PET Big Mouth Boston Bottle. The highly popular Big Mouth Boston dropper bottles are now available in V3 style, meaning the tip is pre-inserted into the cap (not included) for easy installation by man or machine. Instead of a plug style tip, the tip now clips onto the outer and inner lip of the bottle neck to prevent the tip from blowing out under pressure. Polyethylene terephthalate (PET) is of the polyester family and has high clarity, good chemical resistance, high impact resistance, and medium rigidity. PET is also light-weight and is used for products containing essential oils. Avoid using PET containers to store products that contain essential oils greater than 5% or fragrance oils greater than 15%. If your oil percentages exceed these respective levels, please consider using glass. These bottles are sold by the case (100 count).