Abstract: Quick-change hole saw mandrel (10) for a hole saw (18); includes drive shank (14) extending along a central axis (C); and mounting end (16) detachable connected to mounting aperture (26) of hole saw (18) and including drive pin (30) for engagement with drive pin aperture (28) of the hole saw (18). The mandrel (10) includes a gripping arrangement (32) insertable through the mounting aperture (26) for gripping the hole saw base (20). In a normally expanded configuration the gripping arrangement (32) grips the base (20). The gripping arrangement is selectively movable to a contracted configuration in which it can be inserted into or removed from the mounting aperture (26). A pilot bit lock selector (44) for selecting between an unlocked mode permitting quick removal and quick insertion of the pilot bit (12) and a locked mode in which the pilot bit (12) is locked against removal.