I cant find the sifaat for Saad
The letters of hams are in the group: فحثه شخص سكت so Saad has hams
The letters of shiddah are in the group: أجد قطٍ بكت The letters in the group of tawasit are in the group لن عمر
صاد is not in either of these two groups, so it has rikhaawah.
The letters of itbaaq are صاد ضاد طاء ظاء so the Saad is in this group.
Besides these characteristics, it also has safeer, and dhalaqah.