1.5 Sand Timer Set: Our set includes 5 shockproof hourglasses in different colors and time units (3 minutes, 5 minutes, 10 minutes, 15 minutes, 30 minutes). Perfect for time management during activities like boiling eggs, eating, reading aloud, morning and evening brushing, playing, showering, bedtime, and office use. 2. HighQuality Materials: The hourglasses are made of thick, durable borosilicate glass, sea sand, and an ABS shell. The timers run smoothly without sticking, and the ABS plastic base is shockproof and resistant to damage. Each timer measures 3.7 x 1.7 inches and stands stably on flat surfaces. 3. Time Management Tool: Our hourglasses are ideal for tracking time during learning and play, helping children develop a strong sense of time. They also assist in effective time management, allowing you to better organize tasks and balance work and life. 4. Note: The hourglass timer is not a precision instrument; please allow for a ±10% margin of error. Occasional sand sticking to the glass is normal. To resolve this, gently tap the bottle or place it in sunlight for a short time.