Check the listing for details. Cue Case Pack - SharkMarks Pool Ball Position Marker Stickers Billiards Practice. Condition: New. Listed at 11.00 USD. I am removing my Amazon listing for these and selling exclusively on eBay. 20 sheets per pack2.5" x 3" pack to fit in most cue casesLaminated stickers are durable and prevent ink transferRemovable adhesive to protect felt and allow reuse SharkMarks are a practice aid for a variety of billiard games, including eight-ball (8-ball), nine-ball (9-ball), ten-ball (10-ball), one-pocket, straight pool (14.1), bank pool, three-cushion carom billiards, and more. The colored circular stickers mark the positions of pool balls, allowing players to repeat the same patterns or racks over and over again until they are mastered. SharkMarks give players a deeper form of practice. Instead of glossing over mistakes, SharkMarks force the player to identify their weaknesses and overcome them. Examples of ways to practice: - Break, mark the ball positions, and run the same rack repeatedly until perfected - Set up difficult runout patterns - Set up patterns from professional games - Set up drills with exact ball positions - Set up proposition shots for gambling - Design trick shots Shark Marks were created with pool players in mind. The stickers are laminated, making them more durable and preventing ink from transferring to the felt or cue/ferrule. The adhesive is removable, so the stickers can be peeled off of felt in one piece (no residue left behind) and reused multiple times.