<p>A magnetic recording and reproducing device for enhancing the operation efficiency by reducing the number of parts and providing an improved structure is provided. The magnetic recording and reproducing device includes a pole base assembly for loading a magnetic tape by guiding the magnetic tape so that the magnetic tape is wound on a head drum and for unloading the magnetic tape by returning the magnetic tape from the head drum; a deck having a guide rail formed thereon, the guide rail including an insertion recess into which the pole base assembly is inserted and a slit connected to the insertion recess to guide the loading and unloading of the pole base assembly; and a deviation preventing unit for preventing the deviation of the pole base assembly inserted into the guide rail.
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