Thailand Streetmap 10.1 - Thai- ->means-->Thailand Map in Thai language.
Thailand Streetmap 10.1 JCV - Thai --> means--> Junction view files for detailed map above
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Thailand Streetmap 10.1 - English- ->means-->Thailand Map in Eng language.
Thailand Streetmap 10.1 JCV - Eng --> means--> Junction view files for detailed map above (but all signs are in Thai language , not Eng.)
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Map in Thai language need Thai font in your device., need Thai keyboard for search function.,
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For Nuvi 1490 :: is not support both jcv files.
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Thai route base map is useful for zoom out function (No Thai route basemap--> your nuvi still work.)
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You can upload both version to your Nuvi and it will be fine.
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