GMF 150 prefilters are multilayer graded density filters for rapid and efficient filtration of samples with high solids content. They are designed with a course top layer (10 µm) and meshed with a finer layer of 1 or 2 µm. Manufactured from 100% borosilicate glass microfibre, the filter is binder free. It is an excellent prefilter for higher particulate loading capacity with faster flow rates.

• Nearly doubles the volume of sample filtered compared to a single density prefilter
• Compared to an unprotected membrane, three to seven times greater sample volume can be filtered
• Higher particulate loading capacity and faster flow rates than uniform prefilters
• Excellent particle retention (both large and small particles)
• Extends life of final filter membrane

When a sample is applied, the multigrade glass filter traps larger particles in its pores or on the surface of the coarse layer, medium sized particles in the interface meshing and smaller particles in the interstices of the fine layer.