Stanley FMHT42355 FatMax Premium Box Beam Level with Hook, 24" Enlarged vial housing for bright lit vials Magnified center block vial for easy readability, with a MaxEdgeBridged Center Vial for continuous marking surface Block plumb vials for accuracy of 0.0005 inches Removeable endcap for flush and accurate markings. Fold-out rafter hook for convenient job-site storage