My problem is that the sliding door to the terrace moved a bit and was blocked. I disassembled it and found that one of the 2 wheels was broken, the metal support.
The photos are of the one that is fine. The measurements of the rectangle are 76 x 16 cm and the distance between anchoring centers (holes) is 64 cm. The measurements of the wheel box is 38 x 38 x 14.
The only reference that appears on the piece is: 3244A