The GlowStreak's ultra-bright color-changing 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. Glowstreak LED ball 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