It's tricky to say definitively "four stars" because the size of stars can vary greatly, and there are many, many stars bigger than our sun. But here are four examples of stars known for their immense size:

1. UY Scuti: This is currently considered the largest known star by radius, with an estimated diameter roughly 1,700 times that of the Sun.

2. VY Canis Majoris: While its size is debated, it's often listed as a contender for the largest star, with a potential diameter 1,800 times that of the Sun.

3. Betelgeuse: This famous red supergiant is a prominent star in the Orion constellation. Its diameter is estimated at around 950 times that of the Sun.

4. Antares: Another red supergiant, Antares is the brightest star in the constellation Scorpius. It's estimated to be about 883 times the diameter of our Sun.

It's important to note that the sizes of stars can change over time, and new discoveries are being made all the time. The vastness of space means we're constantly learning more about the incredible range of stellar sizes.