We have had a small number of a white version of the Apple MFi certified PC061 key fob beacon come into stock. This beacon supports one of iBeacon, Eddystone-UID, Eddystone-URL at any one time, the mode being changed by quickly double clicking the button. Clicking the button once turns it on and off. It remembers the last used mode.
This beacon is waterproof and weighs only 11g. It comes with a special metal tool for opening the case and replacing the battery. The battery should last 6-12 months depending on the advertising rate.