The ME700 pedals are essentially the replacement for the M530 pedals that have been in Shimano's lineup for nearly a decade, and they're 7.7mm wider and 1.2mm thinner than their predecessor. Along with the extra width, there's an elevated rear portion that's designed to increase the amount of contact with a rider's shoe for better power transfer.
The pedals have an aluminum body, a chromoly axle, and use Shimano's proven cup and cone bearing system. The claimed weight is 486 grams.