This is a Hase Kettwiesel Handbike arm-powered tricycle, with Heinzmann electric assist. It’s about 10 years old, but in good working order. It’s got an 8-speed hub gear and Speed Drive, for 16 wide-range gears.
The Heinzmann system uses the bombproof Classic motor with a throttle on the hand grip. It all works happily, though I can’t guarantee the lifespan of the battery.
New, a trike like this would be about £8000. £3000 ono.