To obtain a jig, especially a slider which can be used for a long period of time by using a carbon composite material reinforced by carbon fiber impregnated with Si having a specified value or higher of compressive strength at a specified temperature, low coefficient of dynamic friction, and superior wear resistance.

The carbon fiber reinforce carbon composite material having the compressive strength of at least 200 MPa at 1,200°C and consisting of 55 to 75 weight % carbon, 10 to 50 weight % silicon carbide is preferably provided with a yarn aggregate whose yarns having a bundle of carbon fibers and carbon components other than carbon fibers are threedimensionally combined and integrated to prevent separation and a matrix consisting of Si-SiC material filled between adjoining yarns, and has the coefficient of dynamic friction of 0.05 to 0.6 and porosity controlled to 0.5 to 10%. The slider combining a bottom 22 and sides 21 on a pedestal 23 can be continuously used even after the manufacture of, for example, 6,000 pipes in the seamless pipe manufacturing line.