1st gen rotors have neither shark fin paddle or battery straps
2nd gen have the velcro battery straps
and 3rd gen have both the shark fin paddle and velcro battery straps
not many of the first gen made it into the UK as they found a problem of batteries coming loose when diving in particular and fixed it very quickly
the shark fin paddle was originaly to be a drop in kit for people that play reball, to avoid jamming troubles) but instead dye put it in as standard however i have had both gen 2 and 3 and not noticed either of them jamming
The shark fin does NOTHING to stop jamming, it just helps to unjam once its already happened.. Ive always found that if my rotor jammed it would be un clearable without disassembly anyway, due to an oval paintball usually..