The spelling of the word "gat chest" can be a bit confusing since it is not a commonly used phrase. In IPA phonetic transcription, it can be spelled as [ɡæt tʃɛst]. The "gat" part is pronounced with a hard "g" sound followed by a short "a" sound and a "t" sound. The "chest" part is pronounced with a "ch" sound followed by a short "e" sound and a "s" sound. Overall, the pronunciation is similar to "gat" as in "gate" and "chest" as in "chess."