Early investors in business-to-business manufacturing platform Zetwerk are sitting on gross returns of as much as 38 times at the upper end of its initial public offering (IPO) price band, while collectively realising about Rs 1,152 crore through the offer for sale (OFS).Zetwerk has set a price band of Rs 143-151 per share, valuing it at Rs 25,583 crore ($2.7 billion) at the upper end. The IPO will be worth Rs 5,012 crore at that price,