The Xcel Infinity LTD 5/4 is a high end winter wetsuit from Xcel featuring thier latest thermal technologies. 

Here's what Xcel have to say:
 
The Infiniti Ltd Combines The Best Of The Infiniti Series With Xcel’s Newest Technologies: Channel Flex And Radiant Rebound. This Latest Advancement Utilizes A Metal Lining Under The Textile That Blocks Cold Temperatures From Penetrating The Outer Layer And Reflects Heat Generated Within The Wetsuit Back toward the Body, Keeping You In A Constant State Of Warmth.
Channel Flex – Weightless, Unrestricted Stretch
Radiant Rebound – Weightless, Unrestricted Stretch
Nanoprene Lite Japanese Limestone – Lighter, Softer, Warmer
Glide Skin Collar – Prevents Flushing
Semi-dry Zipper – Magnetic Closure
Engineered Fit System – Fits Like A Second Skin
Back Knee Flex Grooves – Prevents Bunching
Fusionx Tape – Heat-pressure Bonded Seam Protection
Nexskin Wrist Seal – Minimizes Flushing
Water Based Glue