"While the basics are the same – for the best – there are some slight differences to note with this new SBGW301. Mostly, Grand Seiko provides a revised case and crystal construction, in order to improve serviceability – and possibly to correct a recurring (yet minor) flaw of the previous generation SBGW231; microscopic bubbles within the glue between the case and the crystal reported by some owners. The new construction, which changes the way the crystal is attached to the case, should solve this. Also, the lugs have been moderately reshaped, so that the SBGW301 will be compatible with the beads-of-rice bracelet of the SBGW305."

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