Since we weigh and examine every single disc we inventory, we also inspect each disc for how stiff and how flat they are. You will see these listed in the disc description tiles. You may see something similar to the following:

Green | Red | S3F3 | 175g

This would mean the disc primary color is green, stamp color red, with a stiffness of 3 and a flatness of 3 and the weight is 175 grams.

Each rating is on a scale of 1-5:

Stiffness:
Stiffness is measured with 1 being the least stiff and 5 being the most.
1 - This would make for an extremely soft disc. Typically found in specialty putters.
2 - Typically still found in mostly specialty putters. Rarely in other molds.
3 - You'll see most discs fall into this category. Brand new premium plastics will fall here.
4 - A very stiff disc, many "firm" putters fall here. Innova's DX plastic is a good example.
5 - May as well just be called wood. These would be the hardest plastics on the market and are physically difficult to bend.

Flatness:
The scale of flatness has a 1 being board flat and 5 being "heartbeat" domey.
1 - Zero shoulder on the disc and is perfectly board flat. Discs this flat are typically specifically designed to be flat.
2 - Still a very flat disc, but a shoulder that raises up is present.
3 - A typical flatness for most discs you see on the shelf. Slight dome but nothing out of the ordinary.
4 - Typically a manufacturing defect. Very domey and when the flight plate is pressed, you should hear an audible "pop".
5 - We reserve these discs for the term "heartbeat". When you come across a disc this domey, you know it. When you press the flight plate you hear a very deep, guttural "heartbeat" sound from the extreme dome of the disc.