• 2.5mm- The maximum thickness allowed under the rules. The term 2.5 is often used in a general way to express the maximum thickness of sponge allowed for a rubber sheet to maintain a total rubber/sponge thickness that is within the total allowed under the rules. Depending on the particular rubber sheet the actual maximum thickness of sponge will probably be something more like 2.15mm or 2.3mm.
• 2.0mm-This is the most popular thickness. 2.0mm combines offensive power with more control than 2.5mm. 2.0mm is also preferred by some spinning or attacking players who use light, medium fast "quick attack" blades, particularly for close-to-the table attacking.
• 1.0, 1.5mm- Thinner sponge rubbers provide maximum control and "touch" for players emphasizing steady all-around play or a defensive style. 1.5mm is sometimes used by quick hitting or blocking players.