Medium - Dogs 15-35 lbs (3.5" Tall x 1" Diameter)
Large - Dogs 30-65 lbs (4" Tall x 1" Diameter)
X-Large - Dogs 60-90 lbs (5" Tall x 1.25" Diameter)
XX-Large - Dogs over 85 lbs (6" Tall x 1.5" Diameter)
As with all toys and treats, do not leave your pet unattended.