Plane configuration

Hi all,
Have just booked our seats for outbound flight to SFO from Heathrow and have a question if anyone could help....
We've booked row 61 a&c on the 747-400 config , they are in the row 4 rows of 2 seats . Does anyone know as I can't tell from Seatguru if these seats have the trays in the seat back of the seat I front or if they are in the arm of our seats?
Thanks
Have just booked our seats for outbound flight to SFO from Heathrow and have a question if anyone could help....
We've booked row 61 a&c on the 747-400 config , they are in the row 4 rows of 2 seats . Does anyone know as I can't tell from Seatguru if these seats have the trays in the seat back of the seat I front or if they are in the arm of our seats?
Thanks