T-carrier technology dates to 1957 and provides data rates that range from 56 and (DS0) to (DS1 or T1), to (DS3 or T3). A T1 line carries 24 voice or data channels (24 DS0s), so customers may use some channels for data and others for voice traffic or use all 24 channels for clear channel data. A DS3 (T3) line carries 28 DS1 (T1) channels. Fractional T1 lines are also available in multiples of a DS0 to provide data rates between 56 and . T-carrier lines require special termination equipment that may be separate from or integrated into a router or switch and which may be purchased or leased from an ISP. In Japan the equivalent standard is J1/J3. In Europe, a slightly different standard, E-carrier, provides 32 user channels () on an E1 () and 512 user channels or 16 E1s on an E3 ().