SSI KnockOut Gun Rope Cleaner for 12 Gauge. KnockOut Gun Rope from SSI allows you to clean residue with a two-pass cleaning system. Each gun cleaning system with this SSI Cleaning Kit include a brush feedline and a washable finished rope. Specifications for SSI KnockOut 2-Pass Gun Rope Cleaner: Manufacturer: SSI Quantity: 1 Condition: New Features of SSI Knock Out Two-Pass Gun Rope Cleaners: Two pass cleaning system Includes brush feedline and washable finished rope Package Contents: Sighting System Instruments KnockOut Gun Rope Cleaner SSI KnockOut Gun Rope Cleaner for 12 Gauge GR12-3