Good product that enabled me to bleed twin calipers on a motorcycle single handed, but let down by the tube being too short, should be at least twice the length had to balance a collection jar on a stool in order to bleed the calipers.
Just attach it to the bleed nipple, open the nut and reservoir and just pump the lever to drain the old fluid. Top up with new and pump until the new fluid emerges. Dead easy. Not sure why the product video shows opening and closing the bleed nipple. It isn't necessary. The non return valve prevents any air entering the system. Makes a scooter fluid change a 10 minute job.