These building blocks reach to quite a height when built (43cm), but are so lightweight and soft that a tumbling tower won't cause any tears
From the maker: 
"Fabelab's popular Soft Blocks have different colours and lots of details to stimulate your little one’s senses of sight, touch and hearing."
Materials: Outer fabric: 100% Cotton, Padding: 100% Polypropylene
Dimensions: 13 x 13 x 43 cm
Washing instructions: Handwash 30 degrees -Do Not Tumble Dry - Do not Iron - Do Not Bleach - Do not Dry Clean