Changing the back windshield wiper blade, also known as the back window wiper, on a car is a simple task that can improve visibility while driving in adverse weather conditions. Start by selecting the correct replacement blade for your car's back windscreen wiper. Lift the wiper arm away from the back window, ensuring it doesn't snap back and cause damage. Locate the release mechanism on the wiper arm, which could be a button, tab, latch, or pin, depending on the model. Release the old blade and carefully slide it off the wiper arm. Take note of how it was attached for reference. Next, align the new back window wiper blade with the wiper arm, ensuring it faces the correct direction, typically marked on the packaging. Slide the new blade into place until it clicks securely. Test the new blade by gently lowering the wiper arm back onto the back windshield and turning on the back windscreen wiper. If everything functions correctly, secure the wiper arm in place. Always consult your car's manual for specific instructions, and if unsure, seek professional assistance.