Purchased in 2024 and used for about 3 months to help put my baby to sleep after birth. I stopped using it when my baby got heavier and have been storing it since. I cannot answer detailed questions about frequency of use, etc., beyond what is stated here. There is no instruction manual, but you can find information on YouTube. Akkiesling Wasabi Regular Type Original (Slim Shoulder Type) Irodori Series The rings are standard brown. There are no noticeable scratches or stains, but this is based on my personal assessment. Please only purchase if you are satisfied after checking the images. There are no pets or smokers in the house, but this item has been stored at home. Please refrain from purchasing if you are sensitive or concerned about minor details. After receiving the item, please check that it matches the description and leave a review. I will fold it up small for shipping.