The product is a set of LEGO instruction books for the 42131 Cat D11 Bulldozer Caterpillar. It is a construction-themed LEGO set that allows children and adults to build a detailed bulldozer model. The instruction books provide step-by-step guidance on how to assemble the set, making it a fun and engaging building experience for LEGO enthusiasts. These are in good, used condition. Buyer pays $6.00 for shipping and handling