For some of the "Journey to Ernie" segments, a second puppeteer (usually Jim Martin) controls Big Bird's right wing. He is concealed by dressing in a body suit the same color as their chroma key background (which cannot be done on the main, non-chroma-key "Sesame Street" set). Big Bird's body suit weighs ten pounds, and his head weighs four pounds. According to writer Louise Gikow, the heat inside the suit is "unbearable, and it's extraordinarily difficult to hold Big Bird's head."