Roman numeral code: ii
Scale notes: 2, 4, 6
Attributes: mellow, warm, friendly
2 is a softer, less energetic version of 4, but with a very appealing 'kindness'. It serves somewhat the same purpose as 4 but in a more subtle way.
Very often a 2 chord can be used in place of a 4 chord and it will work, but it will have a feel that is much less bold. 2 fits into chord progressions more or less in the same way that 4 does, but it can also precede or follow 4. Like 4, 2 usually returns through 5 to 1.
6 and 2 are both minor mode harmonies, but 2 has a little more power than 6.