[Naimc]

Hi. New here and first time doing something myself on a car

I have a 2011 520d and the boot spring needs changing as I feel the boot is close to going straight through the window!

I had a look at some videos and posts online regarding what I needed and I ordered the part.

Now where I am confused is that all the videos I've seen they're all replacing just the right spring so I assumed there was only one.

I ordered the spring with the part number 51247204366. I had a look at my car and I noticed there is also a spring on the left side. Upon more research the part I ordered is left side and not right. The right side part number is 51247204367.

Can anyone shed light on if I need to replace both, or just either the left/right? And are both the sides the same or interchangeable or does it have to be the specific part number?

Many thanks!

Edit: upon some more research I found out one is tension spring and one is return spring. Which one did I order and which one is the one I need? My boot doesn't have auto close