These blocks are transparent in the colored part which makes them perfect for color exploration or building structures where the light can shine through them. A piece of paper on the opposite side as the light comes through allows tracing around the shape of the structure. They also make great windows in unit block construction. The size is the same as unit blocks.
I received the blocks today for my one year old son and he loves it. he played all day with the blocks. They are big which i like. I wish they cam in different colors or if there was an option to pick specific colors. Overall i am pleased with product