Feb 8 (Reuters) - Two blank-check firms formed by investor Mark Ein are aiming to raise about $600 million in their initial public offerings (IPO), regulatory filings showed on Monday.

Capitol Investment Corp VI, the sixth special purpose acquisition company (SPAC) backed by Ein, said it would sell 20 million units, comprising shares and warrants, priced at $10 apiece in its IPO. (https://bit.ly/2YZfb1u)

The seventh blank-check firm, Capitol Investment Corp VII, said it would sell 40 million shares at the same price. (https://bit.ly/3a2veln)

Ein worked at Carlyle Group, Brentwood Associates and Goldman Sachs Group Inc before setting out on his own as an investor.

His prior SPACs have invested in a range of firms including real estate investment trust Two Harbors, specialty cruise operator Lindblad Expeditions and PR Newswire owner Cision and NESCO, a provider of specialty rental equipment.

A SPAC, a shell company that raises money in an IPO before later merging with a privately held company to take the latter public, has become many investors' structure of choice over the past year.

Citigroup and Deutsche Bank Securities are underwriters on the lastest offerings. (Reporting by Noor Zainab Hussain in Bengaluru; Editing by Ramakrishnan M.)