Part datasheet in PDF for the MPSW45, an NPN Darlington transistor, rated in the file name at 40 V and 1 A. The high current gain of a Darlington pair makes it handy for relay, lamp and solenoid drivers driven straight from logic outputs. The document gives pinout, saturation voltage, gain and power dissipation so you can confirm the part or select an equivalent. Remember that a Darlington drops more voltage when saturated than a single transistor, so a substitute should match that behaviour. Any PDF reader will display it.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
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