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Product Description
The original Airfix/Mainline version of the 21 ton Hopper wagon contained a specially shaped weight that is missing from some of my DAPOL versions which this item is designed to replace.
This should be sandwiched between the underframe and body of the wagon which simply clips together. To fit you may need to trim a small moulding pip in the centre of the chassis and/or the similar one on the body.