I got three of those too and can highly recommend them, which is why I also mention them as an example here → Zigbee networks: how to guide for avoiding interference and optimize for getting better range + coverage
Note that IKEA makes and sells different models of their “IKEA Tradfri Signal Repeater” depending on which country you live in, however, so far the only real difference between the models is the power-plug (and firmware version that it ships with) → https://www.google.com/search?q=IKEA+Tradfri+Signal+Repeater