LIPPED HORN RING : http://griproyal.com/shop/product/alum_black_horn_ring_lipped/
BOXED HORN RING : http://griproyal.com/shop/product/alum_black_horn_ring_boxed/

http://griproyal.com/blog/post/new-product-release-lipped-and-boxed-black-aluminum-horn-rings/