Societe Generale has launched a structured note linked to four popular H-shares. Currently being marketed in Hong Kong, the SG Excel notes have a maximum life of one year and promise to pay investors a maximum 3.1% a month.

The payout is similar to an accumulator in that investors get the best returns when the worst-performing stock of Sinopec, China Mobile, China Communications Construction or China Merchants Bank trades within a fixed range. For the note to survive until the one-year maturity, at least one of these stocks has to be trading below its starting price at the end of each month.

This is because the top of the range, or the callable price, is set at 96% of each stock's initial price. If all four stocks are trading above this level at the end of any month the note will redeem early, paying investors back 100% of their principal plus the relevant coupon payment. In other words, the note will knock out after one month unless one of these super-charged China stocks falls in value.

That isn't very likely. So far, this year's worst-performer is Sinopec; up a mere 160%. The other three are all up more than 220%, with China Communications Construction up 270%.

Even so, how long the note survives depends on timing. If investors had bought a product like this early in the year it wouldn't have redeemed until the end of May thanks to Sinopec's weak start. However, most of the time the note would have knocked out at the end of the first month, in which case investors get their principal back, plus the coupon.

The first coupon is guaranteed and the subsequent ones are dependent on all four stocks ending the quarter above the bottom of the range, which is set at 85% of each stock's initial price. If one of the stocks dips below 85% on the observation date, no coupon is paid that month. The coupon rate depends on the currency the note is bought in: the US dollar notes pay 3.1% and the Hong Kong dollar notes pay 3%.

Finally, there is a barrier level at 65% of the starting price that acts as the second line of defence in what SG calls the "double cushion mechanism", which gives investors two chances to get their principal paid back in cash rather than shares if the note reaches maturity.

The first cushion is the usual monthly test of whether all four stocks are trading above the strike price. If they are not, the second cushion kicks in, which requires that none of the four stocks have dipped below the barrier level since the start of the investment. If both tests are failed investors get paid back in the shares of the worst-performing stock, bought at the strike price, which will be higher than the price it is trading at.

The notes are being sold by banks throughout Hong Kong and are on offer until November 9. The minimum investment is $3,000 in the US dollar notes and HK$30,000 in the Hong Kong dollar notes. They are expected to be issued on November 21.

Clearly targeted at retail investors, the marketing flyer even offers free supermarket coupons to subscribers û spend HK$50,000 and get HK$50 off your next trip to ParknShop. Investors who prefer to shop elsewhere can take the inducement in cash if they so desire.