With wrist extension, your wrists are bent up and back such that the fingers are higher than the wrist joint. This greatly reduces blood circulation through the wrist and hand and can quickly cause pain, fatigue and numbness. Most traditional keyboards have a positive 10 degree slope from front to back that promote wrist extension. Unfortunately most keyboard users do not demonstrate perfect keying technique, but rather drop their wrists into a dangerously extended posture over the front edge of the keyboard and onto the work surface.

Solution
In order to reduce/eliminate wrist extension the Kinesis Maxim offers removable, padded palm support which positions your wrist in a completely neutral position - at the same elevation as your forearm and hand.