Select an option directly in the attribute.

[OptionsValueButtons(0.5f, 1f, 1.5f, 2f, 2.5f, 3f)]
public float floatOpt;

Or add labels for these values

[PairsValueButtons(
        "<icon=d_scrollleft/>", Direction.Left,
        "<icon=d_scrollup/>", Direction.Up,
        "<icon=d_scrollright/>", Direction.Right,
        "<icon=d_scrolldown/>", Direction.Down
    )]
public Direction direct;

[PairsValueButtons(
    "<color=brown>Broken", 0,
    "<color=green>Normal", 1,
    "<color=blue>Rare", 2,
    "<color=yellow>Legend", 3
)]
public int quality;