Nokia is readying the Treasure Tag, a proximity sensor accessory for Lumia handsets that uses a combination of NFC and Bluetooth to track personal items, reports The Verge.

NFC is used to pair the accessory to an NFC-enabled device while an accompanying app will show the location of the Treasure Tag on a map using Bluetooth.

Treasure Tags will have around six months of battery life and come with a strap, designed to enable the device to be attached to a bunch of keys.

The launch is set to coincide with Nokia's upcoming Amber software update, which will see Bluetooth 4.0 LE — now marketed to consumers as Bluetooth Smart — support added to its Lumia Windows phones, The Verge adds.