Easy to install, gentle on walls, securely fixed, and provides strong support. Exclusively for gypsum board walls (9.5mm or thicker). Cannot be used on soundproofing boards. The removal leaves only small pinholes, which are not very noticeable, making it especially useful for rental properties. WAKAI Strong Push Pins for Gypsum Board Walls, Tack-n, Pack of 3 3 pieces per pack x 5 packs I still have stock, so I can add more for 350 yen per pack. Please comment if you'd like any.