The SB31 kit is for Two beaded skin. (I've got the three beaded skin.) I purchased SB 31 kit. I've placed a total of two (one on each wing) of the large 4" inspection holes & plates. Presently I'm considering placing an additional six-2 1/2 inch inspection holes & plates (3 on each wing). I feel it will do the job of inspecting the wing spars with the use of a Boresope. Now I'm stuck with the balance of a new SB 31 kit. (now all painted too) Anyone wishing to purchase it from me (Less 2 rings & 2 cover plates) It's yours for $125. including shipping USA Hey! It's a good deal too. The complete kit sells for well over $225. from Univair Prof. Ed
