The GlowStreak's ultra-bright red LED core is bounce activated, waterproof, slobber-proof, and includes replaceable batteries. It's ideal for the ball-obsessed dog who wants to play fetch all day--and night. PRODUCT DETAILS Durable LED Ball is great for nighttime play Motion activated - bounce to turn on Auto shut-off after 10 minutes of inactivity (5 minutes of glow followed by 5 minutes of flashing) Durable rubber construction Waterproof - it floats! Run time: 35 hours 2 replaceable CR2032 batteries included Diameter: 2.5" | 63mm Weight: 3.9oz | 112g