Need help determining length of Rexton receiver please


Have a Rexton receiver left, blue, that says 2M.
Having trouble figuring what the length is, other than 1,2 3,4.
I looked at the chart on Rexton but it gives no length.
Its about 1 1/16 inch from loop to tip, see picture.
I assume Siemens receiver will also work ?
Thanks. not buy used hearing Aids off Ebay, Costco

Look carefully at the pictures in their largest size;

You have a size 2 Medium power.


My impression is that 2 is the length and that M is the power level. It’s blue, so it’s a left one, so you need a left 2M.