Just built a small wheelbarrow planter for back yard. Painted it with opaque redwood stain. (2 coats). Stenciled sides and back using "Dry" Acrylic stensiling paint. Have a can of clear Acrylic spray sealer to use to protect the stenciling but I don't think it alone is adequate for exterior oudoor protection. My question is: What kind of clear EXTERIOR product can I spray or brush on all to protect from weather. (I am afraid to use something that will remove or damage the redwood opaque stain or the stenciling and Matte finish).