While the EMU is solely intended for the microgravity environment, where weight is not an issue, the I-Suit's planetary role makes weight a critical factor. By replacing the EMU's fiberglass Hard Upper Torso (HUT) section with a soft upper torso, or SUT, and by using lightweight titanium in place of stainless steel for load-bearing metal components, the I-suit weighs only 65 pounds (29 kg) without its life support backpack or thermal/micrometeoroid layer, compared to 107 lbs (49 kg) for the EMU. The suit also features a graphite-epoxy shoulder bearing housing, demonstrating the use of this material in place of aluminum. Replacing all the suit's bearing housings with graphite-epoxy would save a further ten pounds (5 kg).