Yes, that all sounds about right. I tried to measure, but I'm none the wiser whether it is exactly 5.3mm or 5.33mm. I did find a manufacturer specification giving the spacing on G5.3, GU5.3, and GX5.3 bases as 5.33mm.
At the risk of getting the discussion all riled up again, MR16 is effectively just as misleading a term as GU5.3. It is used and interpreted as meaning an MR16 on a GU5.3 base, but they are also available on GU10 and small or large screw bases, and I've even seen a picture of one with a bayonet cap.
Until LEDs came on the scene, most lamps with a GU10 base were effectively MR16s, multi-faceted reflectors 16/8" across. I'm not an insider but I imagine it was decided, or just came to pass, that they would be marketed as GU10s rather than MR16s for a GU10 socket to avoid confusion (and perhaps encourage the notion that they were "better"?). Until recently, lamps with a GU10 base that were anything other than an MR16 were exceedingly rare. Likewise, lamps with a GU5.3 base that weren't MR16s were also rare although there are some GU5.3 capsules, effectively an MR16 without the reflector.
Yet now we have lamps with GU10 or GU5.3 bases which are not multi-faceted reflectors, in many cases longer than a standard MR16 lamp, and in a few cases also wider. Calling them GU5.3s in the absence of any other name is at least accurate if not a very helpful description. Many people will not care so long as they have two pins and run on 12V - they're unlikely to stumble across the 5V or 24V versions by accident and those that need a GU5.3 capsule will probably know how to find them. Many others will be surprised not to get a shiny (possibly colourful since they were nearly all dichroic, for good or bad) glass bowl and some have been very disappointed to get over-size metal space-ornaments that won't fit their holders. So maybe they have to be called GU5.3 and people will just have to get used to it.
Does anyone else think that the biggest problems with LED lamps is that 99% of people have no clue which one they need to buy?
At the risk of getting the discussion all riled up again, MR16 is effectively just as misleading a term as GU5.3. It is used and interpreted as meaning an MR16 on a GU5.3 base, but they are also available on GU10 and small or large screw bases, and I've even seen a picture of one with a bayonet cap.
Until LEDs came on the scene, most lamps with a GU10 base were effectively MR16s, multi-faceted reflectors 16/8" across. I'm not an insider but I imagine it was decided, or just came to pass, that they would be marketed as GU10s rather than MR16s for a GU10 socket to avoid confusion (and perhaps encourage the notion that they were "better"?). Until recently, lamps with a GU10 base that were anything other than an MR16 were exceedingly rare. Likewise, lamps with a GU5.3 base that weren't MR16s were also rare although there are some GU5.3 capsules, effectively an MR16 without the reflector.
Yet now we have lamps with GU10 or GU5.3 bases which are not multi-faceted reflectors, in many cases longer than a standard MR16 lamp, and in a few cases also wider. Calling them GU5.3s in the absence of any other name is at least accurate if not a very helpful description. Many people will not care so long as they have two pins and run on 12V - they're unlikely to stumble across the 5V or 24V versions by accident and those that need a GU5.3 capsule will probably know how to find them. Many others will be surprised not to get a shiny (possibly colourful since they were nearly all dichroic, for good or bad) glass bowl and some have been very disappointed to get over-size metal space-ornaments that won't fit their holders. So maybe they have to be called GU5.3 and people will just have to get used to it.
Does anyone else think that the biggest problems with LED lamps is that 99% of people have no clue which one they need to buy?
