The Borei submarines are approximately long, in diameter, and have a maximum submerged speed of at least . They are equipped with a floating rescue chamber designed to fit in the whole crew. Smaller than the Typhoon class, the Boreis were initially reported to carry 12 missiles but are able to carry four more due to the decrease in mass of the 36-ton Bulava SLBM (a modified version of the Topol-M ICBM) over the originally proposed R-39UTTH Bark. Cost was estimated in 2010 at some ₽23 billion (USD$734 million, equivalent to US$863 million in 2020 terms), in comparison the cost of an SSBN was around US$2 billion per boat (1997 prices, equivalent to over US$3 billion in 2020 terms).