Weight Disks
General Notes:
Weight Disks marked with a ¹ are not legal under WBO Organized Play Rules.
Takara Eight- series Weight Disks are generally more sharply-molded/less polished than their Hasbro counterparts, which is most noticeable with Eight Wide and Eight Heavy. Generally they are also slightly heavier as a result, but there is a lot of cross-over in both directions (well below average Takara WD's, Well above average Hasbro WD's), even with Eight Wide. The polishing difference is still slightly noticeable on Wide, Balance and Heavy, as well as some Ten Wides from Hasbro, but the difference is much less noticeable and there is no significant weight difference. This appears to change as production moves to China.
SonoKong Weight Disks from Pre- Engine Gear System Plastic Beyblades (i.e. not from their GBlade line) are slightly smaller than their Takara and Hasbro counterparts, and as a result are significantly lighter. In terms of molding they resemble Takara's versions, with even less polishing. See SonoKong Pre-G Series Cross-Brand Compatibility for further details.
In general, Sono Kong weight disks are less polished and more likely to have excess metal that hasn't been removed after molding.
Sono Kong's Engine Gear System era Ten Wide and Ten Balance (I haven't seen a Ten Heavy like this, but it is possible I just don't have any Sono Kong made ones) are stamped with two 'G' logos (for G-Blade, their marketing name for the line) on their underside, and are the same dimensions as their Takara and Hasbro counterparts. They are much more prone to Weight Variation than other brands, with significantly heavier examples of Weight Disks than have been seen from Takara/Hasbro. Keep in mind, however, that below average weight SonoKong WDs are also possible - just like MFB 4D releases from them, this is a case of greater variation, not necessarily greater average weight.
Also note that Sono Kong sometimes repackaged Takara-made parts with their own Instructions, Stickers and Boxes during the Engine Gear era. Thus, it is not uncommon to receive Takara Weight Disks from SonoKong - if the parts are marked Made In China rather than Made in Korea, then it's almost certain you've got a Takara-made Weight Disk too.