When converting the Parkwood Warwell kit to a six bolster bogie wagon using my six bolster conversion sets, these tools may come in handy. The little ones can be used to try the holes you cut in the planked floor of the kit to accept the central bolsters. It saves using the bolsters themselves while the holes are still being perfected, which risks breaking them. The larger part will then fit into the holes you have cut in the planking and prove everything is square (or show where it isn't) and also show you where to position the other bolsters. This could be handy where the bolsters which sit above the sloped part of the floor require the outermost floor plank to be removed and the exposed edge filed straight. As long as you don't break it, this gadget is re-usable so you only need one, no matter how many bolster wagons you make this way. There are two of the smaller part, so you have a spare of the one most likely to be lost between the (real world) floorboards.