The pn is 220 271 00 98
It's about 3/16 thick, about 2 1/8 long and 1 1/2 wide with 2 rows of 1/2" slots cut into it, seems to be plastic but has a magnet embedded into it.
On newer trannys that have it installed, they put it into a similar dimensioned part of the rear of the pan, the outline being made up of the reinforcement ribs stamped into the bottom of the pan.

Gilly