This is a DS18B20 precise temperature sensor. The sensor achieves an accuracy of +/- 0.5C over most of it's operating range. The sensor is used over a 1-wire 5V TTL interface. This makes it ideal for general measurements.
The ROBOTIS HN07-N101 Servo Horn is a servo horn set for the RX-24F, RX-28 and MX-28 Dynamixel servos. This is the new mounting pattern which is included with all N101 series Dynamixels. It comes with a thrust washer for added stability.