Having spent a few hours poking around REI and searching the internet for new thermal underwear (and cold weather gear in general) I am reporting what I found out as a follow up to the earlier thread in case others might be interested. It looks like there are two forms of new thermal underwear: (1) polypropylene microfleece such as Capilene, sold by Patagonia http://www.patagonia.com/ , and various clones and (2) polyester fleece (more velour like) such as Polartec's, Power Dry and Power Stretch, http://www.polartec.com/mm/ , which are sold by various retailers in different forms. Both types come in different weights and have wicking and fast drying qualities. Polartec's website has links to many retailers who sell their fabrics including Patagonia which is certainly at or near the top in quality and price. I have not actually seen the Polartec fabrics but from the descriptions they sound heavier than the thin smooth Capilene type. From reading reviews and ads it seems that my old ideas on underwear (I am used to cotton, acrylic and wool) are out of date. Cotton is universally condemned and almost everyone had negative things to say about wool too including Merino wool (not as warm or dry or light as the new synthetics and looses its shape after washing). I don't know about that since I used to hunt in the Northeast and wool pants and top saved the day many times because it works when wet and it wore like iron. The prices for the new synthetics run from about $20 per top or bottom on up to $130 or more for a Patagonia lightweight Polartec top. REI has Patagonia products and their own line of microfleece underwear. Both look and feel very similar. Problem is they only have lightweight and medium. I want to try heavy weight since astro-work means standing still and I almost froze at the All AZ Star Party way back in early Oct. Several reviewers of Capilene underwear noted that it retained body odors to an annoying degree; yuk. Since folks discussing the Sentinel trip are talking about a 2-3 day outing that nasty feature does not sound good!! Thus I am going to try the Polartec underwear from Cabelas which has the heavyweight versions at prices way below Patagonia. [FYI one of the Cabela's tech people recommended their military weight polypropylene underware as the warmest available. Campmor sells this item as Duofold Expedition Weight and Cabelas sells the same outfit under their own name for about $20 for the top or bottom.] The best websites I saw besides the above were http://www.cabelas.com/ , http://www.llbean.com and http://www.campmor.com/ plus several of the sites linked to Polartec's webpage. Regards, Bill Wood Fountain Hills, AZ -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.