This mask is interesting because it has bird's nest as an ingredient! Swiftlet's nest extract, to be precise, and it's their saliva. Apparently, swiftlet saliva has moisturizing and conditioning properties, as well as wound-healing capabilities. The bird's nest extract use in this mask is most likely a dried, sanitized version, and the harvesting of their saliva and whatnot apparently does not endanger the little swiftlets at all, so I feel much better about using this mask! Bird's nest extract is an age-old ingredient that has been used in Chinese medicine and skincare for centuries to help with wound healing and maintaining youthful skin, while helping improve skin texture and prevent signs of aging. It's even eaten as a soup or put in desserts - in China, bird's nest soup is a delicacy, and is considered one of the most expensive animal products consumed by man, with a small bowl of soup costing anyway from 30-100 USD. The nests, when consumed, are supposed to help with things like collagen production, aiding in digestion, and improving the immune system. That's a lot of claims for some bird spit, but there you have it. The star ingredient, Swiftlet Nest Extract, is the third ingredient from the top, which isn't bad at all! There's also glycerin, a known humectant that attracts water to the skin and helps keep it moisturized, the Swiflet Nest Extract (1000mg). It also contains betaine, which helps smooth the skin and give it a more youthful appearance without the stickiness typically associated with glycerin-based products, as well as sodium hyaluronate, which is a super-moisturizer, basically, that can attract and hold 1000x its weight in water. There's also botanical extracts, ceramides, and witch hazel, oh my! It was very saturated, there was enough essence inside for two days, at least. It had a light, unoffensive "mask" smell that I associate with all typical sheet masks, and was on the thinner side, which meant it adhered to my face really well and didn't slip and slide everywhere. This mask was a bit heavy for my skin, and the essence didn't absorb right away, so I'm glad I used it at night instead of the morning. When I woke up, my skin felt incredibly soft and looked a lot more hydrated, though! Although, to be fair, I have oily, dehydrated skin, so I'm kind of easy to moisturize. Repurchase? ...Possibly. It wasn't a bad mask by any means, I actually really enjoyed the soothing, moisturizing effect it had on my skin.