It’s always about to pop off when you’re wearing the 509 FZN Merino Party Suit. This one-piece base layer is made with warm, breathable, temperature regulating Merino wool, and can be worn under a mono suit or a jacketpant combo to help keep out drafts, snow, and party blockers. An elastic waistband keeps it in place while a near-360 zipper allows you to efficiently drop trou when nature call.