'Head Texture'
2xx by 2xx [whatever it is
512 x 512

If the sizes get bigger what pixels is the 'head texture' the 2k one?

There are three resolutions of head texture items: 128x128, 256x256, and 512x512.

128x128 being the lowest quality, 256x256 being medium quality, and 512x512 being the best quality.

The "head texture" you speak of is of the lowest quality (128x128).

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