Molded Glass Rock Slides are individually hand cast by master craftsmen. They have the same features as our brass Rock Slide®, with the knuckle cutout, finger rest and tapered interior. They fit almost exactly like their brass counterpart, but are slightly longer. The main difference is that they are much lighter and faster, making them suitable for use on an electric guitar. Thanks to our unique tapered interior design, they have enough mass to light up your acoustic guitar.