TECHNOLOGY FOCUS - POLYMERS - Preferred Property: The fluorine-containing elastomer composition has Mooney viscosity (ML1+10) of 2-30 at 100degreesC, and 120 or less at 121degreesC, and is less than 0.4A+4 and 4 or more, where A is compounding quantity of filler. Preferred Compound: The fluorine-containing elastomer consists of a structural unit derived from 1 or more monomers chosen from perfluoro (alkylvinyl ether) may having ether-bond property oxygen in alkyl group, and a structural unit derived from vinylidene fluoride and hexafluoro propylene, tetrafluoro ethylene, ethylene, propylene and chloro trifluoro ethylene. Preferred Composition: The fluorine-containing elastomer composition comprises fluorine-containing elastomer (A) (in weight parts) (100), organic-peroxide curing-agent (B) (0.1-10), and further a polyfunctional property vulcanization support agent (C) (0.1-20) and filler (D) (50-300). Preferred Compound: The filler (D) is carbon black, natural graphite, artificial graphite, silica, silicate, boron nitride, aluminum nitride, magnesium oxide, alumina and/or carbon nanotube. EXAMPLE - 10 Wt.% of perfluorooctane acid ammonium aqueous solution (in g) (290), pure water (720) and diethyl malonate (0.6) were stirred under reduced pressure. Then, vinylidene trifluoride (20) and hexafluoro propylene (51) were added and temperature was raised to 80degreesC. Subsequently, ammonium persulfate salt (0.02) dissolved in pure water (0.6) was pressed-in with nitrogen gas, and polymerization was initiated at pressure of 2 MPa to obtain emulsion having polymer particles content of 1233 g. The aqueous dispersion of polymer particles (33.5), 10 wt.% of perfluorooctane acid ammonium aqueous solution (19.1) and pure water (1324) were stirred under reduced pressure. Then, vinylidene trifluoride (171) and hexafluoro propylene (729) were added and temperature was raised to 80degreesC. Subsequently, APS (0.068) dissolved in octafluoro-1,4-diiodo butane (5.96) and pure water (15) were introduced with nitrogen gas, and polymerization was performed for 3.4 hours to obtain emulsion containing polymer (1899). The emulsion was dried at 130degreesC, solidified and dehydrated by aluminum sulfate for 15 hours to obtain elastomer (543) having weight average molecular weight of 48000, number average molecular weight of 94000, molecular weight distribution of 1.9, Mooney viscosity (ML1+10) of 11 at 100degreesC.