Sippers have been designed to avoid the messy spills due to straw not closed when it is not used. the easy screw on lid seals the straw to avoid leakage of liquid. the silicon straw is also designed in such manner to protect the child's delicate mouth from injuries in teeth and gums. the straw is also very easy to sip any type of liquid. the curve shape and grip of sipper allows easy handling to children and parents