Thickened Size. 0.45 in, on the one hand, compared to 0.2 in, our filter is more durable, on the other hand, it will not be too thick to make the litter box run wrongly. Compatible Models: This carbon filter is designed for litter-robot 4, slightly thicker on one hand more durable to absorb more odors, on the other hand will not be too thick to make the machine malfunction.
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