Developed by Pierre Guillaume, a contemporary master bow maker from Brussels, Belgium. This rosin offers an excellent balance of grip and smooth sound quality. The rosin itself shows no noticeable damage. The wooden case has been in use for several years, and the wood is very clean, but the label sticker shows signs of wear. Please check the condition as shown in the images. The rosin inside was recently replaced with a new one from a Guillaume tin and has been used for one month. It is crack-free and in good condition. This is a rare item in a beautiful wooden box, and the wooden box is discontinued, making it difficult to obtain. The rosin inside the wooden box is the same as the rosin in the tin, so refills are possible in the future. The rosin is a very good product, and I loved using it because the wooden box is beautiful and has a warm texture when held, but I am selling it because I have switched to homemade rosin. This is a set of the rosin itself and the wooden case.