Wing morphology strongly affects flight performance which may consequently decline during feather moult due to the creation of feather gaps in the wing. Hence. the size and shape of moult-related wing gap may directly affect flight capacity. Here I examined the rare divergent primary moult sequence compared to the more common descendant moult sequence. https://www.roneverhart.com/Mizuno-Prospect-GXC105-Youth-Catcher-s-Mitt/