[If] one slaughters with a hand sickle, with a flint, or with a reed, his slaughtering is valid. All may slaughter, and we may always slaughter, and we may slaughter with anything, except with a harvesting sickle, a saw, teeth, or a nail, because they strangle. [If] one slaughters with a harvesting sickle using a forward motion, Beis Shammai declare it invalid, and Beis Hillel declare it valid. But if they smoothed out its teeth, it is like a knife.