Telescoping Leg Provides Added Table Rigidity When Hollow Chisel Mortising or Performing Other Heavy Workpiece Operations. \n \nThis special telescoping leg extends to 27� to 42-1/2" and features a notch in the top that slips around the table lip. Then it locks on to the Table with a single knob. Adjust the leg for table height with a quarter-turn of the leg. It keeps your worktable from deflecting when you are be exerting more downward pressure during mortising or drilling operations. Originally designed for the MARK V 500 / MARK V 505 / MARK 4. We found Installing a single leg under the table of the rest of the MARK Models is much faster than using two standard telescoping legs on connecter tubes.