I also received a bunch of Pearl stems from Nitto. These are cold-forged masterpieces and maybe the most beautiful stems of all time. Here's the scoop:
Quill Diameter: 22.2 mm for 1" threaded steerers
Clamp Diameter: 26.0 mm
Extension Angle: 71-degrees
Available Extensions: 8, 9, 10, 11, and 12 cm
Price: $65 each
Note: Because Nitto measures the extension length through the center of the extension rather than the top, their sizes wind up being a little smaller. So, a 8 cm Nitto stem will be the same length as an 8.7 cm stem measured as most other companies do. Generally, you can buy one size shorter than usual.