chest minecart

{
  "format_version": "1.12.0",
  "minecraft:entity": {
    "description": {
      "identifier": "minecraft:chest_minecart",
      "is_spawnable": false,
      "is_summonable": true,
      "is_experimental": false
    },
    "components": {
      "minecraft:type_family": {
        "family": [ "minecart", "inanimate" ]
      },
      "minecraft:collision_box": {
        "width": 0.98,
        "height": 0.7
      },
      "minecraft:rail_movement": {
      },
      "minecraft:inventory": {
        "container_type": "minecart_chest",
        "inventory_size": 27,
        "can_be_siphoned_from": true
      },
      "minecraft:is_stackable": {
        "value": true
      },
        "minecraft:physics": {
      },
      "minecraft:pushable": {
        "is_pushable": true,
        "is_pushable_by_piston": true
      },
      "minecraft:conditional_bandwidth_optimization": {
        "default_values": {
          "max_optimized_distance": 60.0,
          "max_dropped_ticks": 20,
          "use_motion_prediction_hints": true
        },
        "conditional_values": [
          {
            "max_optimized_distance": 0.0,
            "max_dropped_ticks": 0,
            "conditional_values": [
              { "test": "is_moving", "subject": "self", "operator": "==", "value": true}
            ]
          }
        ]
      }
    }

  }
}