I have taken this picture for another post on anther forum, but I think this will also serve great as a reference here: [UPDATE] Now with larger pictures and more detail. Middle sized tips of all sort. Top row (left to right): UE foam (discontinued, replaced by Comply T500), iM716 black long foam (similar to ER4 foam), Shure yellow foam (Universal Fit Foam), ER6i comply foam, Ety tri-flanges, UE bi-flanges (a.k.a. small or regular bi-flange), X3i bi-flanges, SA6 bi-flanges, RE1 bi-flanges (a.k.a. big bi-flange) Bottom row: Shure clear PVC (Clear Flex), Shure gray silicone (Gray Soft Flex), Shure black foam (Olives!), Typical Sony/Panasonic/Audio Technica silicone (a.k.a. generic wide nozzle), UE silicone. Dimension of inner opening: [--UPDATE 6/24/09--] Top: Shure black foam (L, M, S) Bottom: Shure grey flex (L, M, S) Side: Shure untrimmed tri-flanges Top: Sony hybrid silicone upside-down (SS, S, SM, M, LM, L, LL) Bottom: Sony hybrid silicone (SS, S, SM, M, LM, L, LL) *Sony Hybrid Replacement Eartips pack (EPEX10A) is made out of SS, S, M, and L -size eartips. [----UPDATE END----] [--UPDATE 6/24/11--] (All middle sized) T100 - Small nozzle. i.e. Fischer Audio DBA-02, Brainwavz B2, Klipsch Custom series, Wesone, Shure, etc T130 - Phonak Audeo PFE T140 - ADDIEM T200 - Semi-wide nozzle. Grado GR8, Ortofon e-Q5, etc. S400 / Tx400 / T400 / Ts400 - Standard wide nozzle - Most lower end Sony and Audio Technica, HifiMan, Sunrise, Monster Turbine series, etc. P series - Westone and Etymotic ER4. Mostly T100 compatible as well. S sereies reviewed here against T and Tx series. Ts series review is here. (Reference: Shure grey soft flex, generic wide nozzle single flange, Sony Hybrid - all middle sized) Shure Black foam (L, M, S) - a pair each. Comply T200 (L, M, S) - a pair each. JAYS foam - universal size, one pair. Generally compatible to any IEM that takes T130 and T140, even to T200 on occasion. [----UPDATE END----] [--UPDATE 6/26/11--] Monster tri-flanges (small, large) - for nozzle diameter 3.5mm and above. Etymotic (small, large) / Westone / Shure - Same / very similar material, for narrow nozzle. * Etymotic tri-flanges come pre-trimmed for Etymotic IEM nozzle length. [----UPDATE END----] [--UPDATE 9/29/11--] Reference: Comply T200 (top) and Shure Black Foam (2nd top). Monster Foam Supertip: White and Black have the same diameter which Black a little longer in length. [----UPDATE END----] Additional Information Shallow vs. Deep Insertion There is no hard definition of how deep an insertion constitutes as shallow or deep insertion. From my personal experience, flanges that are inserted less than 1cm in depth can be called shallow insertion; More than 1cm than it should be called deep insertion. Based on this kind of classification, UE foam, Shure yellow foam, Shure clear PVC, Shure gray silicone, Shure black foam, typical Sony/Panasonic/Audio Technica silicone, and UE silicone are all shallowly inserted. The rest are deeply inserted. Generally, the deeper the eartips are meant to be inserted, the better the isolation they will give (better isolation = better SQ). However, deep insertion often means they will be less comfortable. Cleaning and maintaining your IEM and eartips (as copied from my IEM guide) Maintaining a clean set of IEM will keep your eartips lasting longer and provide a better seal. First of all, remember that there is no better way to keep an IEM clean than cleaning your ear canal regularly. For universal IEM: If at any time the eartips does not maintain a grip on the earphone nozzle, discard the tips, clean the IEM nozzle and replace the tips with a new set. If one or both side of the IEM stop working or has reduced volume, change the IEM’s filter (see note 1) or clean the nozzle opening with the provided tool. For custom IEM, clean the acrylic shell of the IEM with tissue and make sure the nozzle isn’t blocked by earwax after every use. Clean the tips and cable when needed (at least once a month). If you exercise with your IEM, you should clean the cable and tips more frequently, especially areas of the cable that come in contact with your skin. This will ensure the longevity of the cable and prevent from skin oil interacting with the cable. Do not use alcohol-based cleaners or those that contain bleach. A damp paper towel with mild soap will suffice. To clean the tips, remove it from the IEM first. To do this, grasp the tips between your thumb and index finger, and twist and pull the tips from the nozzle. Do not pick at the tips as it may cause it to tear. Carefully clean the IEM housing and nozzle to remove any wax or oil residue. Be careful not to let any moisture enter the nozzle opening. If moisture does enter the IEM it may not perform properly. If moisture does cause one or both IEM to function at reduced level, leave the IEM out of their carrying case in a dry, well-ventilated area, which should allow the moisture to evaporate in 24 to 48 hours. Soft plastic tips should be washed in warm soapy water when they become oily or dirty. Un-washable foam tips should be discarded if they become dirty, dry out, or no longer compress and expand fully (see note 1 below). Shure black foam tips (known as ‘Shure olives’ among head-fi’er, introduced in Spring 2007) can be washed by simply wiping off any debris from the outside of the tips with a warm, damp paper towel. ALWAYS let the IEM and tips completely dry before placing the tips back on the IEM. Make sure that the tips slides all the way on to the base of the IEM’s nozzle (past the nozzle bump if there is one.) Note 1: Experiment done by Head-fi’er has shown that by gently dipping the foam in pharmacy’s grade peroxide solution (also know as H2O2 / eardrop, often used for dissolving earwax) for a short period of time (15 minutes or so) can partially clean the foam and extend its lifespan. The same principle applies to user removable filter and earwax clot on nozzle opening. In regular use, most foam tips will degrade with in 1 month (that is assuming you keep a clean ear canal). Shure Olives are known to last more than 1 month (some even reach 3 months with regular cleaning). YMMV. Eartips and SQ Generally speaking, foam tips have a warmer, bassier, but less detail sound than silicone / PVC. Deeply inserted silicone eartips will have a bassier, slight more detail sound than shallowly inserted tips.