Tech Spray 1991 Brush Attachment. The Brush Attachment is an economical unit designed for precise control of cleaning applications. Simple in design and structure. The Brush attachment allows convenient. One-handed cleaning. Special fittings. Hoses. And holders. The Brush Attachment is simply installed on top of the aerosol container. The valve allows complete control of the amount of solvent applied. A variety of brushes are included for use with the Tech Spray 1991 Brush Attachment. The medium horse hair brush Tech Spray 1992 is recommended for most electronic cleaning applications. The long horse hair brush Tech Spray 1993 is designed for more sensitive areas. The brass brush Tech Spray 1994 is designed for aggressive cleaning of stubborn soils and precious metals.