A: Those are 1/2" square balusters so you need shoes that fit 1/2" square balusters. Flat Shoe = 16.3.19 and Angled Shoes = 16.3.2
A: These balusters are not intended for exterior use. However, some customers have applied a sealant over them for weather proofing.
A: The hollow version of the baluster, 16.1.4-T, comes in Ash Grey. The solid one does not.