 In addition, the weapons were installed along the line of the wing's dihedral, rather than parallel to the ground line as in the earlier Mustangs.The wing racks fitted to the P-51D/P-51K series were strengthened and were able to carry up to of ordnance, although bombs were the recommended maximum load.Later models had removable under-wing 'Zero Rail' rocket pylons added to carry up to ten T64 5.0 in (127 mm) H.V.A.R rockets per plane.