2 AA batteries
2.25 in x 1.5 in /5.75 cm x 3.75 cm (teaser)
1.25 in /3.25 cm (diameter small ring)
1.5 in /3.75 cm (diameter medium ring)
2 in /5 cm (diameter large ring)
3.5 in x 1 in/9 cm x 2.5 cm (probe)