Speakers question.

[TheSyntaX]

Hey, at the moment I have default speakers in car.
1 of my speakers in left passenger door is blown/broken/torn it works but makes irritating vibration sound. So I decided to replace both, drivers door and passenger doors speakers. I installed new radio/player in car few days ago and on box it says:
Power output: 4x 20W RMS
Does that mean that each speaker must be 20W?
I am looking at cheap basic speakers but they all say:
Max 180W power
3-way coaxial driver

So will they fit?

[S W]

There are usually 2 different power ratings listed on audio equipment. RMS and Max. Just ignore the Max rating, all that really means is that the piece of equipment can deal with that much power for a split second. RMS means it can deal with it for a continuous amount of time. So if you have 100 watt RMS speakers, you would want a 100 watt RMS amp.
Now that is a very basic explanation of it but it should suffice. There is no harm in under-powering your speakers so if your speakers are 50W RMS and your deck is 20W then that is fine. But like I said, just ignore that Max power rating as it really is a garbage rating.