Insulation resistance: more than 10m Ω between housing and plus end wire red color at 500V DC. Dielectric strength: no damage can be found 600v AC.2 seconds, between housing and plus end of lead wire. Material: Frame: UL94V-0 70% P.B.T.+30% F.R.P Impeller: UL94V-0 70% P.B.T.+30% F.R.P Bearing system: ball bearing or sleeve bearing Operating temperature:-10 to+°C70 Storage temperature: -40 to+°C70 Opreating voltage: rated voltage±15%.