Comparison : Item # T301 Half Hard 0.0180" x 12" x 12",
Item # T301 Half Hard 0.0180" x 12" x 18",
Item # T301 Half Hard 0.0180" x 12" x 24",
Item # T301 Half Hard 0.0180" x 24" x 24",
Item # T301 Half Hard 0.0180" x 24" x 36",