It's likely you've heard about this special kind of acid before. It's found in almost any moisturizing serum worth its salt and, like Weir mentions in the video, it's "comforting, hydrating, definitely not as dangerous as it sounds." But the appeal goes far beyond the fact that the pipette makes Weir feel like a "doctress" when he's using it. It also helps his skin trap in loads of moisture so it stays plump and soft for the TV cameras.