The start position, roller pad, and spring-assisted back pad on the pin Selected Line Leg Extension adjust easily from the seated position, providing a comfortable fit and supporting proper exercise mechanics.The spring-assisted back pad easily adjusts from the seated position so the exerciser can properly set up the unit while seated.Both the start position and roller pad easily adjust to ensure the unit fits the exerciser for proper form throughout the exercise.The weight stack uses a simple pin adjustment that exercisers can easily reach from the seated position. Assembly size:1372*1252*1500mm, gross weight:238kg, weight stack:100kg; Steel tube: 50*100*3mm