Expand foundational unit block sets with just the pieces your builders need more of. Made to align with the same mathematical dimensions as traditional unit blocks, these add-on sets are designed to be used as an enhancement to foundational sets.
I grabbed these to top up our bin because we kept running out of the little cubes mid-build. They align perfectly with the blocks we already have, so towers stay flush instead of wobbly. Two kids and a whole afternoon later, still no complaints.
These add-on pieces match the unit blocks we already had perfectly, so the new ones blend right into the bin. My youngest finally has enough small blocks to build a whole castle without stealing from his sister's set.
My kids kept fighting over the last few blocks, so grabbing this 8-piece set finally solved that. They line up perfectly with our older unit blocks, same dimensions and everything, so the towers don't wobble.