A new fleet of Victoria Line trains has been unveiled as part of a £750m upgrade to the line.
People are being consulted on the new design
The proposed design, on show in Euston Square Gardens, central London, is set to run from 2009.
The Victoria Line revamp, by Tube maintenance firm Metronet, includes a new signalling and control system, new tracks and a more robust power system.
Frequency and capacity of the trains will rise significantly once the work is completed in 2013, said Metronet.
There will be 43 trains operating at peak times when the new trains come on line compared with the current 37.
Stephen Hall, of Metronet, said the new fleet will be larger, faster and more comfortable with improved accessibility and security features.
"When the upgrade is complete in 2013, the frequency of rush hour trains is likely to increase by 17% and journey times should improve by 16%," he said.
Members of the public are being invited to give their view on the new design at the show room in Euston.
The eight-carriage trains will be designed and built by Bombardier Transportation in Derby.
The upgrade is part of the £17bn Metronet is investing in the Tube over its 30-year contract.