Product Category Description:

Binder-free VWR glass fiber filters feature fast flow rates, high-loading capacity, wide thermal tolerance, and excellent precipitate retention. Available in three grades: Grade 691 is an ideal filter for radioimmunoassay of weak beta emitters by scintillation counting, and for filtration of precipitated proteins, cells, and cell debris. Also used for gravimetric determination of airborne particulates. Grade 693 is recommended for use in dissolved and suspended solids testing in sanitary water analysis procedures. Grade 696 is used for monitoring specific pollutants (e.g., Hg in water), and in marine chemistry to filter particulate components in sea water. Also used in RIA procedures and for harvesting lymphocytes during incorporation trials.

Specifications for Whatman Glass Fiber Filters 28297-978 Grade 691 :

Diameter, cm:		2.4
Unit:		Pack of 100
Porosity:		Fine
Flow Rate:		Fast
Particle Retention, Grade 691:		1.5 µm
Particle Retention, Grade 693:		1.1 µm
Particle Retention, Grade 696:		1.2 µm

(Please note that the description and stock photo may not correspond to the specific model listed above)

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