This "accessory" is not limited to only Giant bikes as there are several other manufacturers of 1.25" steerer tubes. Works perfectly on my Canyon Grail AL 7 gravel bike. Would be nice if the MacRide seat had the option to choose the size needed instead of having to pay more for the 1.25" adapter, but it is what it is. Hope this helps someone out there!

The spacer works as advertised and is a must have if you have a Giant bike with Overdrive 2

This spacer is exactly what it says. The special thing about it is that the good folks at Mac-Ride make it. From a Giant owner who has painfully shopped for a stem and headset, this part is greatly appreciated.