Tip — drag the ring around the centre to turn it either way; it snaps to the nearest 45°. A plain click turns it 45° clockwise (shift+click or right-click for anticlockwise). Click the FLIP half of the hub to turn the upper half over: its four pieces reverse order. The pieces are solid, so only the front is shown.
σ ε
EvenOdd
Apply a move sequence
Conjugates — record a sequence α, then undo it with α⁻¹nothing recorded