new SearchRequest<Project>()
{
    Scroll = "1m",
    Slice = new SlicedScroll {  Id = 0, Max = 5 }
}

{
  "slice": {
    "id": 0,
    "max": 5
  }
}

s => s
.Scroll("1m")
.Slice(ss=>ss.Id(0).Max(5))