The Akai X-355 is a vintage reel-to-reel tape recorder manufactured by Akai in the 1970s. It features a 4-track double speed, 2-channel design and is capable of recording and playback in both mono and stereo formats. The X-355 offers various control options, including adjustable pitch control, tape counter, and VU meters for monitoring audio levels. It also supports recording on both 7-inch and 10.5-inch reels. The X-355 was designed for professional audio applications and is highly sought after by vintage audio enthusiasts.