Chooch Ent. #8321 HO Scale Cascade Tunnel Single-Track Portal - 4-3/4 x 4-7/8"
Chooch Ent. #8360 HO Scale Single-Track Random Stone Tunnel Portal - 5 x 4-3/4"
Chooch Ent. #8350 HO Scale Double-Track Cut Stone Tunnel Portal - 6 x 5-1/8"
Chooch Ent. #8340 HO Scale Single-Track Cut Stone Tunnel Portal - 4-1/2 x 4-1/2