Birchwood Casey Brass Black Metal Touch – up. Fast – acting liquid used by gunsmiths to blacken or antique brass copper and bronze parts. Easy to apply with no dimensional change. Often used to mark cartridge cases to identify loads. Excellent for blackening name plates plaques castings sculptures and other home workshop and hobby uses. Color varies depending on alloy and can be highlighted if desired. 3 or 32 fl. ozs. State Size. Order Today! WARNING: This item cannot be shipped to Canada. Please check your State County and City laws for restrictions before ordering this product. Birchwood Casey Brass Black Metal Touch-up