Review on INKESKY Shimano RD-TZ31-A Rear Derailleur: High-Performance 6/7 Speed Hub Bolt Mount for Mountain Bikes by Jack Bhowmik

This was incredibly difficult to install. The fixed bracket that attaches to the bike had to be adjusted to get the bike indexed on the sprocket and it was very difficult to get all the gears in place. The springs in the derailleur or not strong enough 2 will cause the trailer to go back into low gears so it will shift normally and when you come back and downshift it will hang in that gear because the spring isn't pulling it down to the next sprocket. I would suggest buying a different switch and saving yourself a headache.