Bowling cent is public ball and special ball two kinds. The structure of public ball is simpler, it is OK that a round core wraps a case again, because this is public the performance of the ball is poorer. And the construction of special ball is more complex, it by inside 3 parts comprise fort of ball nucleus, weight and crust. Ball nucleus is to ensure the filler such as the plastic or other pottery and porcelain of standard weight. Weight fort is body of synthesis of heavy qualitative plastic particle. It has have the figure such as fort, diamonds, bulb, dawdle. This kind of special appearance is to make sure the ball has compensation of a weight after bore, produce lopsided weight. Crust uses You Luding viscose normally or colophony is raw material, the man-made balata that says normally namely and get together fat, in recent years special ball uses active colophony to make case more. This 3 parts close together through the treatment craft of high accuracy, make the appearance the smooth, sphere that has certain hardness and standard weight. The function of all sorts of special balls is different, what crust weighs with core again is fasten, cent waits big He Xiaozhi of the coefficient that hook a gender a moment. Become all sorts of different surface roughness plus the outside burnish of the ball, the smooth area that says normally namely and wear arenaceous face. Can suit all sorts of different lane faces. Bowls production technology is very sophisticated. Want above all pouring the core of the ball, in the pattern that noting fort surely together next, irrigate the fort of outpour ball. In the mould that outer casing secures after fort make it, outpour is whole ball. Undertake polishing finally, engrave the identification marking such as a brand. Outside the identification marking such as the brand name that the surface of the ball removes a ball, brand, number and weight fort, not be patient of any uneven phenomena. The ball divides a top (on) , bottom (below) , before, hind, left, right 6 place. The identification marking such as fort and dot of centre of gravity is in the coping of the ball. The hardness cent of the ball is soft, medium, hard 3 kinds. Defend couplet provision by international: 72 ～ are soft ball 76 degrees, 77 ～ are neuter ball 85 degrees, 86 ～ are rigid ball 90 degrees, 90 degrees of above are extremely rigid ball.

Have appropriative sclerometer to the measurement of the hardness of the ball, it is multi-purpose in formal match, if the ball is too soft,will be cancelled to use.