Description These are reactor quick twisting caps, made of high-grade ABS material, which are safe and durable and can be used with confidence. It is suitable for all kinds of DIY reactors, and can be directly screwed to carbonated beverage bottles for use without air leakage, which can bring you a good experience. Easy to use. Just screw the bottle on the drink bottle. Easy and sealed without letting the air out easily. Features -Color:Light Brown -Material:ABS -Size:3.30X3.30X3.00cm/1.30X1.30X1.18in -High class ABS for issuing great resistibility of rub, so it is durable and practical. - system bottle caps are designed for planted tank use. -It has a simple design, but very practical in use, bring much convenience to you. -It can directly screwed to carbonated beverage bottles for use, safe and durable, no air leakage. -The installation method is simple and will not take you too much time. High class ABS for issuing great resistibility of rub, so it is durable and practical. system bottle caps are designed for planted tank use. It has a simple design, but very practical in use, bring much convenience to you. It can directly screwed to carbonated beverage bottles for use, safe and durable, no air leakage. The installation method is simple and will not take you too much time.