Screw Jacks

You know I am not a DIY person but my Wild Boar is :p.  The other day he was doing some work  in the porch and he asked me to get him his screw jack from his carpentry cupboard in the backyard.  Gosh, I asked him to describe to me how screw jacks  look like .  He was telling me how it looks like and after all his explanation and description I am still not sure how it looked like. So in the end, I told him to go get it himself :)  Save me a trip to the backyard and since it is his stuff, he should go get it himself . I know I would surely make a blunder and give him the wrong one . Of course, I know kitchen stuff better than him but not DIY stuff ... LOL!