The Texas Instruments ULN2003AD is a 7-channel NPN Darlington array designed for driving relays, solenoids, and other high-current loads. It features a 500mA current capability per channel.
The ULN2004ADE4 is a 7-channel NPN Darlington transistor array from Texas Instruments. It features 500mA output current per channel, low-side inverting configuration, and is housed in a 16-SOIC surface-mount package.