Buy gbl online. Gbl Cleaner Contants 99,99% Pure Gamma- Butyrolactone And is of German quality. You can use our Gbl cleaner for the following applications: - Removing paint and graffiti. - Remove rust. - Removal of ink stains. - Removal of oil stains. - Removing grease and fat. - Removing glue. - Cleaning of rims. - Destroy weeds (biodegradable).