KOSS Spark Plug earphones

Inexpensive (bought for about $12, although now identical model seems to cost more) earphones from Koss. Some love them, some hate them - sound quality is good in general, although there may be too much bass depending on preferences. They are relatively big for earphones and this kind of design is not too ergonomic. My biggest issue with them is degrading foam - this is "memory" foam that is supposed to fit in ear when squeezed. It should retain sqeezed form for a few seconds, but with time it looses this "memory" property and starts behaving like plain rubbery foam. It probably would take few months, but after time you won't be able to fit them in ear canal at all. Second issue: this plastic is brittle (or gets brittle with time?) - one of my earphones cracked after being dropped on hard floor, so I had to glue it with 2-component resin.

Two identical in size foam sets were included in my package. Additional ones are somehow expensive - I'm seeing them at $12 (+ shipping cost as you won't find them at local shop) for 6 pairs at the moment.

These earphones were covered with lifetime warranty, although there is processing fee that makes it not viable economically (processing fee is basically same as earphones cost).

 Plastic tubes under foams:

 Old trick to restore these earphones is using hearing protection foams like these, 3M model 1100 to replace original foams. They are available in every drug store for $0.25 a pair (or less, about $0.10 a pair if buying in bulk).

 Cut foam to match tube length, make hole for the tube

Overall, sound isolation is not necessary better than for earphones with silicone seal, but from my use foam has less tendency to slip out of the ear after time and can sit in place for hours.