As far as it's known, there are three Denso type lightweight starters that have been introduced to the market over the last 15-18 years. For decades the standard infamously sounding wind starters were the only norm aside from unpredictable and non stock looking aftermarket starters.
These factory starters dating back to the 60's or earlier weighed a ton usually at 16-18 Lbs. My forehead is still recovering from the knocks. LOL.
The first lightweight types that I came across were the 90's van versions that weighed in the hood of 10-11 Lbs.
After those came the 8-9 pounders and then the current one that is at a high 7's in weight. Heat shields have been removed and the winding housings are a tad smaller along with the snout and its bosses IIRC.