Ball Bearing Type

The DEF28 telescopic linear guide has a cross section approximately 28 mm ( 1.1") high x 26 mm  (1.0") wide, basically a square cross section.  One side of the assembly attaches to your structure while the other side attaches to your moving...

The DEF43 telescopic linear guide has a cross section approximately 43 mm ( 1.69") high x 44 mm  (1.73") wide, basically a square cross section.  One side of the assembly attaches to your structure while the other side attaches to your moving...

DSS 28 series product.  Last number is stroke-out length.  Number before that is the overall collapsed length of the product.