We hope that these designations will help you describe your project.

L - fixed length, fully editable
(optimum widths 77cm, 99cm, 121cm, 142cm, 148cm)

h - total height of the frame (adjustable feet available)
Under the frame top, highlighted in yellow, are 2cm x 2cm steel sections. The thickness of the top is 15mm. If you want to fit something under the frame that is, for example, 32cm high, the height of the frame should be at least 1.5cm higher, and where the profiles are, 3.5cm more, so h = 35.5cm

d - width of the sliding frame

D - width of the extended frame
For example, if the sliding frame has d=81 cm, it can be extended to a maximum of D= 140 cm.
d=71 cm -> D= 120 cm
d=81 cm -> D= 140 cm
d=106 cm -> D= 190 cm