| 摘要 |
<p>A lock for retaining one or more ladders or trestles to a rack comprises a hook which hooks under the rack while the shaft of the hook extends through and beyond the one or more ladders or trestles and a cross beam with a flange at each end which receives the shaft of the hook and sits on and around the one or more ladders or trestles and a handle which also receives the shaft of the hook and secures the cross beam in place thereby fastening the one or more ladders or trestles to the rack and wherein said cross beam is extendable to fit a variety of ladder or trestle sizes.</p> |
