Jumbo Blocks are made right here in the USA! Design Plastics Inc. produces Jumbo Blocks and all the accessories at their main plant. Large blocks are 3-1/4" tall by 3-7/8" wide and 7-3/4" long. The half size blocks are 3-1/4" tall by 3-7/8" wide by 3-7/8" long. Set includes 54 blocks. (45 large blocks, and 9 half-size blocks.) Plus an assortment of plastic windows! Colors: Red, Yellow, Blue.