Long version Kaavie Off Camera E-TTL Flash Remote Cord for Canon SLR & DSLR, Canon 580EX, 580EX II, 550EX, 430EX replaces OC-E3 (Electronics)
Ordered instead of the original Canon twice as much (or so), the quality seems very good; on first use I had slipped the spade-head switch on the flash shoe, and therefore no contact, I thought it was a failure! Too bad there is not some kind of "key