Radios

10pcs 433Mhz Antenna

For RFM69 Modules

10pcs 868Mhz Antenna

For RFM69 Modules

10pcs 915MHz Antenna

For RFM69 modules

10pcs NRF24L01+ 2.4GHz Wireless Transceiver

This is what enables your sensors to communicate wirelessly across a nominal range of 60 meters.

Bluetooth module

Wireless Bluetooth RF Transceiver Module serial RS232

Shielded nRF24L01 PA+LNA

A shielded nRF24L01 PA+LNA with SMA connector (needs external antenna)

NRF24L01+ Socket Adapter Board

Another adapter for Arduino Pro Mini 5V that provide 3.3v regulated power to the radio. Solder free.

Quad-band GSM/GPRS Shield

SIM900 GSM/GPRS Shield for Arduino UNO/MEGA/Leonardo

RFM69 433Mhz Transceiver

HopeRF RF69 module. Select frequency band on aliexpress.

RFM69 868Mhz Transceiver

HopeRF RF69 module. Select frequency band on aliexpress.

Wireless Transmitter and Receiver Link Kit Module 433Mhz

Let your sensor control 433Mhz stuff. See petewill's example here.