Shift Robotics has launched a new version of its Moonwalkers shoes / motorized roller skates that claim to boost the speed of your natural walking gait.

Their top speed is still 7mph, but they’re over a pound lighter on each foot — 4.2 pounds compared to 5.3 pounds — thanks to a new “magnesium alloy powertrain.” The Aero are also 20dB quieter as a result of there being eight fewer wheels underfoot and a new “Neodymium magnet based motor.”

Despite a streamlined design, the new $1,199 Moonwalkers Aero are slightly more expensive than the originals, which are still available for $1,049.

The advertised average range on a full charge remains the same at around seven miles, but that will depend on the terrain, whether users are going uphill or downhill, and their size. The Moonwalkers Aeros can support users up to 220 pounds, and the company says the new version works more efficiently in hot environments with a longer range thanks to a new “thermal and regenerative management system.”

Shift Robotics says that “every visible part” on the Moonwalkers Aero is user-replaceable and that they’re designed to fit better with shoes ranging in size from a women’s six to a men’s 12, with a new optional spacer that’s available in two sizes.

The original Moonwalkers are now positioned as the more rugged version ideal for uneven terrains featuring bumps and cracks, with the Aero intended for indoor use, such as warehouses with smooth concrete floors. They also connect to a mobile app that includes preset modes for indoor, city, and sport, with a customization option letting users modify their acceleration profiles to their comfort level.