As all Oxygen Sensors are not created equally O2Sensors.com.au offer almost exclusively* Direct Fit Oxygen Sensors.
Direct fit type oxygen sensors are just like in the Original Equipment (OE), as opposed to “Universal” fit sensors, which can be used in multiple applications. Direct Fit sensors are easy to install with No Wire Cutting or Splicing required, with made to measure cable lengths and original connector plugs fitted.
Direct Fit Oxygen Sensors are matched to the vehicle application (make, model and series) and cannot be mixed and matched. They are easy to install with made to measure cable lengths and original connector plugs, which make the sensor suitable for the actual vehicle specified.
Direct fit Oxygen Sensors incorporate:

DIRECT FIT Oxygen Sensor Plug Connector Samples
Universal oxygen sensors were widely used in the early years of vehicles that were equipped with oxygen sensors. It is impractical to offer a universal sensor for many vehicle applications due to many factors including heater types, ground types and other characteristics. Also, some manufacturers may use white wires for example for the heater and others may use black, thus it is best to use a direct fit connector to avoid confusion.
Incorrect use of a universal sensor can result in serious damage to the engine management system, including failure of the engine control unit (ECU) or the catalytic converter
A UNIVERSAL Oxygen Sensor:
*Single wire Universal Sensors may be offered for some vehicle models by o2sensors.com.au where a direct fit replacement is not readily available; this applies only to a few sensors in our massive range of over 600 oxygen sensors.