VIAHART Brush Blocks Interlocking Plastic Bristled Blocks The bristles interlock from multiple angles to connect the pieces | Cultivates spatial thinking, mechanical, engineering skills | Recommended for ages 4+ Every jar of Brush Blocks includes more than 35 pieces, including four working wheels! The pieces range in size from 1.75 Inches across to 3.5 Inches and are .75 Inches tall SIZE AND WEIGHT | Product Measures 4.75 x 4.75 x 7.35 in inches | 12.1 x 12.1 x 18.7 in centimeters | Product Weighs Approximately 1 lbs / 0.5 kgs | These dimensions and weight do not include the packaging 30 day no questions asked return policy and FREE returns! | Watch our video to learn more about this product: youtube.com/watch?v=qXk1n18EfLo