US Patent 10420401 Pet health monitor with collar attachment and charger

In one embodiment, a collar attachment comprising a disk having a first collar band loop integrally formed with the disk along a first arcuate perimeter portion of the disk and a second collar band loop integrally formed with the disk along a second arcuate perimeter portion of the disk that is opposite the first arcuate perimeter portion of the disk; a keyhole in the disk; friction attachment means formed in an underside of the disk and configured to receive at least a first tab of an attached device and to snugly hold the first tab against the underside of the disk after rotation of the attached device in the keyhole.