2,563. The Intersection of the Sinews

Hilchos Shechita 8:13

The intersection of the sinews is a spot in a domesticated and a wild animal above the heel, from which butchers hang the animal. It has three white sinews: a thick one and two thin ones. The intersection of the sinews goes from where they begin and are firm and white to where the whiteness goes away so that they start to redden and soften. This area is about 16 finger widths long in an ox.

Hilchos Shechita 8:14

A bird has 16 such sinews that start from the lowest bone – the extra claw – and go to the end of the foot, which is scaly.