Automatic N-gauge couplers for 24.5 t coal hoppers

These rapido-style self-acting couplers are the same as the ones in my N-gauge / 2mmFS kits of 24.5 t British Rail coal hoppers, so you can buy spares if you need them. Because of the restricted space between between the ends of the hopper bottoms and the bufferbeams, and the need for grooves to chase the end stanchion supports into the top of the chassis for strength in the printed model, end stanchion, they are a slightly not quite the same as, and are not interchangeable with, the couplers for my other chassis kits (9'6"wb or 12"wb for 21t end-tipping mineral wagons). The hooks should be able to lift and fall in their mountings, so if they are all seized absolutely rigid when you receive them, try no more than careful cleaning with warm soapy water to free them, and if that doesn't help, return them for a refund. If you break them, you may understandably lose that option. So far I have only ever received one duff lot, and I broke all but one of them investigating ways to free them, or drill out the pivot to free them and replace it with a rod. If they don't fall freely enough to drop by gravity, you can feed a shim of bent plastic through the slot in the top f the mounting, to act on the back of the coupler as a spring.