First you need to see the size of the reed switch, refer below,
Large: glass tube length 30 ~ 60mm, glass diameter 3.5 ~ 6mm.
Medium: glass tube length 20 ~ 30mm, glass diameter 2.5 ~ 3.5mm.
Small: glass tube length 5 ~ 20mm, glass diameter 1.5 ~ 2.5mm.
In addition, the shape of the reed, the structure of the contact portion, etc., are often different designs, but as long as the reed is used, it belongs to the range of a reed switch.
As we can see, there are many styles of size. So the options can be more.
Please contact us for more suggestions of target size to use.