[technogeek019]

is a class 4 lexar micro sd card compatible with a nokia class 4 micro sd card adapter

[rockstarzzz]

Going by what is out there being sold as compatible with Nokia Lumia 620, yes.

Nokia Lumia 620 Memory Card (Micro SDXC) & Accessories - From 4.50

[OzRob]

Just as a general point here, ALL micro SD and micro SDHC and micro SDXC cards should be compatible with the Lumia 620. Some may perform better than others, but all should be compatible. That's the whole point of a standard.

[technogeek019]

Just as a general point here, ALL micro SD and micro SDHC and micro SDXC cards should be compatible with the Lumia 620. Some may perform better than others, but all should be compatible. That's the whole point of a standard.

U may hav got this wrong but i am asking if one brands of micro sd card is compatible with a micro sd card adapter of a different brand ( but of same class )

[OzRob]

U may hav got this wrong but i am asking if one brands of micro sd card is compatible with a micro sd card adapter of a different brand ( but of same class )

As I said, micro SD, micro SDHC and micro SDXC are STANDARDS. Therefore all micro SD[xx] cards of the same standard are effectively interchangeable (between phones and adaptors). BUT companies don't always interpret standards identically, so occasional issues do crop up, so there's no 100% compatibility guarantee - only about 99%.