Described herein is a holding basket (100) for containing an inner basket (200) for holding at least one medical item for processing having a top end (102) and a base end (104) comprising: an essentially rectangular base (110) and side walls (120, 122, 124) extending from the base (110), two rims (130, 132) each disposed on a first pair (120, 122) of opposing side walls, two windows 140) each disposed on a second pair opposing side walls (124) configured for manual access for slidable removal of the inner basket (200), wherein the holding basket (100) is configured for stackability or nestability with an adjacent holding basket (100′, 100″).