When I was young, my mom kept what we called ‘the spanking stick’ in a kitchen drawer. It was a polished piece of wood whose purpose should be obvious from its name. It was about a foot and a half long.
One end was narrower than the other for maybe a third of its length, forming a kind of handle, but even at its widest it wasn’t more than two or three inches. I don’t know where mom got it – perhaps Dad made it in his workshop. Its arrival certainly pre-dated my memory, having been used on both of my brothers’ bottoms before my own.