1. Metal Glide Bar: Made of high quality durable 304 stainless steel; it can provide excellent sustain, excellent intonation and clear and bright sound2. Glass Glide Bar: Made of seamless heat-resistant glass, high-quality boron silicate is processed by heat treatment and annealing3. Silky blues portamento4. Adopt integrated design, safe material5. Size: about 6 x 6 x 2.5cm6. Weight: 130g