The effect of particle sizes on the reinforcing properties of locally sourced filler (P.K.S) on rubber compound (foot mat) was investigated. This was also compared with the characteristics of kaolin filled vulcanisate. Various particle sizes of kaolin and palm kernel shell (P.K.S); 75µm, 150µm, 212µm and 300µm were used. Different physical tests relating to the required service conditions (hardness and compression set) were carried out on the vulcanisate. From the results, it was observed that P.K.S (pH of 6.25 and moisture content of 10.9%) at particle sizes 75µm and 212µm had better hardness and compression set resistance and this could be recommended for products where these properties are desired.