In the Gong line, the SP models are versions with less width and volume.
For instance, compare the Zero 9'
http://gongsupshop.com/epages/box1707.sf/en_GB/?ViewObjectPath=%2FShops%2Fbox1707%2FProducts%2FGON7SUPZERO90PS to the Zero 9' SP:
gongsupshop.com/epages/box1707.sf/en_GB/?ViewObjectPath=%2FShops%2Fbox1707%2FProducts%2FGON7SUPZEROSP90 The Zero is 29.5" wide, the Zero SP 26.75" wide.
Note that Gong LongSUP models have quite different personalities, well detailed on the web site (that now have an english version!). The "Introduction" section details the real character of the board, this is not just a marketing blurb, but the accurate description of the characteristics by the shaper himself. Very useful to compare different Gong models.
Basically:
- The Zero is an agressive performance board: noseriding on fast/big waves, and projecting the board forwards in turns. it must be driven hard
- The Freak is the "all around" performance model, in the spirit of the NFA, that can be turned by carving or by pivot/stalling, and correct mistakes. The Freak SP may be the closest in feeling to the Nalu.
- The Soul is a retro noserider for fast waves: pivot turns, lock in the curl and adapts its speed to the wave
- The Neverstick is a retro noserider for slow waves: pivot turns, lock in the curl and adapts its speed to the wave
- The Moblog is a new kind of LongSUP, with the tail of a Tomo board (tail + channel) for extra tail power on weak waves, and being able to lock the tail under the curl in noserides, even without an US Box. It must be turned as a shortboard, well on the tail.
PS: I have a Freak, and, although wide at 30.3", it means the volume could be distributed to have rails as thin as a longboard, and in mini hossegor tubes the thin rails bite quite make it for the width. It is in no way a run-of-the-mill beginner board. The NFA line is the one for beginner/intermediate riders, with more comfortable rails.
Note that the weights are accurate. For instance the Zero SP 9' is given for 7kg±5% means that your board really will weight between 6.65kg and 7.35kg (naked: add ~600g for the pad). Each board is weighted at the factory and the weight written on the cardboard, boards heavier than the specs are sold at a discount. This a full carbon, PVC sandwich board, quite strong, and with an insane precise drive on the water.