These printable GR1 and GR1A original and extended top dry rock phosphate hopper models in HO 1:87 and N 1:160 scale just need trucks and couplers. These rotary hoppers have been used to haul dry rock phosphate since the early 70s and were upgraded by CSX with higher capacity around the year 2000. The models consists of printable STL files--some with molded on grab irons and some with dimples for drilling and adding wire grab irons. The HO scale bodies measures 128mm in length. Best suited for resin printing. All the HO models use the same roof and roofwalk files.