Sizes: 4 mm Estimated Pieces per lb. : 5500 Material: Solid Soda Lime #3000 Glass Packaging: One Pound Plastic Jars Specific Gravity: 2.49 g/cm³ Temperature of Transformation: Tg 440 ºC Softening Temperature: Tt 505ºC Coefficient of Linear Extensions: 20-100º 75.0 x 10-720-300º 102.8 x 10-7 Diameter & Sphericity Variation: Maximum ±10% of the Glass Ball Diameter