1, Aluminum coil for channel letter. 2, No need extra trim cap covering ... .2, Specail double folded block design aluminum channel letter coil: We call it" special" because of the double folded ... from a channel forming machine. Specifications:1). 50 Meters per coil, 100 meters per carton.2). Height: 50mm, 60mm. ... Gold, Mirror Silver, White, Black and Red. aluminum coil or trim cap for channel letter