... . Size of channel is for the following: sizewall thicknesslength1-5/8"x1-5/8" (41.3x41.3mm)1.5mm, 2.0mm, 2 ... ,3.05m,5.8m,6m We also can produce the Wall thickness from 1.5mm to 2.7mm.Stock length is 10 ... and 20 feet(3000mm,3050mm and 6000mm,5800mm).Special length are available upon request.Our factory have many different sizes ... both of material and products. strut channel galvanized slotted 1-5/8"