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Generic, cheap, and it fits

HMF Carbon filter 3789

A generic activated carbon filter that fits litter boxes and compost caddies with a filter slot — the cheapest way to keep a hooded box fresh.

HMF 3789 activated carbon replacement filters

HMF Carbon filter 3789

A generic activated carbon filter that fits litter boxes and compost caddies with a filter slot — the cheapest way to keep a hooded box fresh.

Type
Activated carbon
For
Compost bins and litter boxes with a filter insert
Manufacturer reference
3789-165MM-S10
Amazon reference
B09XBPCY3N (identical on 5 markets)
EAN
4010537378929
  • Genuinely generic: one cheap part for the kitchen caddy and the litter box
  • German brand with stable availability
  • Fit is a matter of cutting rather than clicking

Best for: Anyone tired of proprietary filter packs for a slot that is just a rectangle of carbon foam.

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Specifications

Type
Activated carbon
For
Compost bins and litter boxes with a filter insert
Manufacturer reference
3789-165MM-S10
Amazon reference
B09XBPCY3N (identical on 5 markets)
EAN
4010537378929

What it is

A generic activated carbon filter, sold for compost caddies and litter boxes that have a filter insert in the lid.

The point of buying the generic one

A carbon pad is a carbon pad. Sold in the pet aisle it costs several times what the identical item costs in the kitchen aisle, and the only real difference is whether it is pre-cut to a shape. Cutting one takes thirty seconds.

Cut it slightly large

A pad that seats under tension seals its slot; one that drops in loosely lets air pass round the edge. That is the difference between a filter working and a filter being present.

What it will not fix

The drawer seal, or a drawer left for two weeks. Filters are the last ten per cent of odor control.

The questions owners ask

Why is a compost bin filter also a litter box filter?

Because both are a pad of activated carbon in a slot, and the slot sizes overlap. Buying the one that is not sold as a pet product is often the same item at a third of the price.

How do I know it will fit?

Measure the slot in your lid and cut the pad slightly oversize so it seats under tension. That is the whole fitting method, and it works better than a loose proprietary pad.

How often should it be changed?

HMF publishes no interval; two to four weeks is the range every manufacturer in this family quotes. Smell is a poor guide, because your nose adapts — use the calendar.

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Elsewhere in the cupboard

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