This is the basic sealed Glass Slide with our proprietary liquid.
Specifications for The LiquiSlide™: The inside diameter is approx. 21.75mm - 21.90mm (this very slight variation is due to being hand made) We at LiquiSlide™ have found this diameter to be the industry standard and most popular for the guitar player (also known as the medium size) and for the majority of players when used with the ring finger (3rd) it will be the perfect, slightly loose to snug fit. It can also be used with the Pinky finger for the classic loose fit.