Good question, I'd like to know too, I have a curved DP stalk that needs to be replaced with an aluminum one. I think my DP stalk is about 1/4" wide.....but it's at home and I'm at work so I can't really measure it from here. There were some measurements on TK409's site but it doesn't really show from which point, it just says RF Stalk 187mm?? Don't know if that includes the RF or not?J-ROCK