Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 66

पतत्पतङ्गसङ्काशः resembled the setting Sun, व्यायतः broad, कपिः monkey (Hanuman), बध्यमानया bound with, कक्ष्यया with the girth, प्रवृद्धः expanded to an enormous size, मातङ्गः इव elephant like, शुशुभे appeared.

The vanara expanded into an enormous size form appeared as though moving like the setting Sun. He looked like a huge elephant bound round the waist.