This is a Piko 38505 G Scale Pennsylvania R/C 25-Ton Diesel Locomotive

Some posts include a mounting pin

Unpainted Metal Parts

but several kits (sold separately) can be combined to make a longer platform if desired

ARRMA AR310484 16.5mm Red Aluminium Wheel Hex (Pack of 2) ProductID_12143453 This is a Piko 38505This is an ARRMA AR310484 Aluminium Wheel Hex 16. 5mm Red (2pcs.). These 16. 5mm Aluminium Wheel Hexes provide a strong and secure Wheel fitting for your ARRMA vehicle. This features Precision manufactured aluminium for reduced vehicle weight and consistent fitting, Anodised red for cool looks and increased durability. This include 2 x 16. 5mm Red Anodised Aluminium Wheel Hexes per pack. Condition: Factory New Operational Status: Functional Original