OLL28 (Arrowhead shape)

S’ (R U R’) S (R U’ R’) (Arrowhead at left back corner)

S (U R U’ R’) S’ (R U R’) (Arrowhead at front right corner)

I was using M’ U M U2 M’ U M for the second case, but I prefer S/S’ turns to M/M’ ones, so I changed it.