Volvo 2007 S80 Owner's Manual page 200

With the wipers in the service position, fold out the wiper arm from the windshield. Press the button on the wiper
blade attachment and pull the wiper blade straight out, parallel with the wiper arm.
Slide in the new wiper blade until it clicks into place.
Check that the blade is securely in place.
206
06 Maintenance and specifications
Wiper blades and washer fluid
Cleaning
NOTE
The wiper blades are different lengths. The blade on the driver's side is longer than the blade on the passenger side.
Clean the wiper blades with a lukewarm soap solution or car washing detergent.
Filling washer fluid