In Tretā-yuga the Lord appears with a red complexion. He has four arms, golden hair, and wears a triple belt representing initiation into each of the three Vedas. Embodying the knowledge of worship by sacrificial performance, which is contained in the Ṛg, Sāma and Yajur Vedas, His symbols are the ladle, spoon and other implements of sacrifice.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
त्रेतायां रक्तवर्णोऽसौ चतुर्बाहुस्त्रिमेखलः । हिरण्यकेशस्त्रय्यात्मा स्रुक्स्रुवाद्युपलक्षणः
tretāyāṃ raktavarṇo'sau caturbāhustrimekhalaḥ | hiraṇyakeśastrayyātmā sruksruvādyupalakṣaṇaḥ
SB 11.5.24