Check the listing for details. 4pcs Coasters, PCB Circuit Board Coasters FR-4 Drink Bar Coasters, Green. Condition: New. Listed at 17.52 USD. PCB coasters can be used as creative gifts, and they are chic gifts for fathers/uncles/brothers, boy-friends, or engineers and computer user at birthday parties, housewarming, and holidays. Widely used in kitchens, bedrooms, dining rooms, study rooms, living rooms, bathrooms, restaurants, bar, cafes, offices and other places to add lovely colors to these places.Specification:Material: FR-4, Immersion GoldPCB Plate thickness: 1.5MMSize: 9 x 9 cm / 3..54*3.54 inchPackage list: 4 x pcb circuit board square coastersAdvantage: This fun drink coaster is made of real PCB material, which is durable and will not deform or crack, and can be used for a longer time. Made of real circuit boards, these PCB coasters are exquisite and beautiful, with rounded corners and clear electronic component circuits.