Track"s concept for the Solid 300C was to provide a ball that not only performs extremely well for higher rev rates but offers a different motion on the lanes than can be used by medium rev rates as well on medium to dry lane conditions. Coverstock: Gen MC (Moderate Continuation). 800 Abranet, 1000, 2000, 4000 Abralon, Powerhouse Factory Finish Polish. Lane conditions: Medium to Light Oil. 12# RG 2. 60 Diff . 039. 13# RG 2. 53 Diff . 055. 14# RG 2. 60 Diff . 052. 15# RG 2. 58 Diff . 055. 16# RG 2. 58 Diff . 055.