The Catapillar D11T Bulldozer LEGO Technic set 42131, with 3854 pieces, is a highly detailed and intricate construction model which is quite a technical build and aimed at adults or experienced builders. It would make an ideal Xmas gift for Lego or construction enthusiasts. It is a fully functional phone app-controlled bulldozer and so provides lots of fun in addition to the challenge if the build. This set is used and has been built once and was on display with other technics construction sets in my collection. It has now been dismantled and carefully bagged into the correct build sequence as per the included instruction manuals. It also comes with the outer box, which does have some damage due to a little damp where it was stored. See photos.
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