The Von Flue choke is a shoulder choke that is rarely seen in MMA and BJJ competition. It is named after Jason Von Flue who successfully used the choke in 2006 during his UFC Ultimate Fight Night 3 match against Alex Karalexis. Since then a number of MMA fighters and BJJ practitioners have executed the submission successfully in competition.
In recent years Ovince Saint Preux has become known for his use of the choke in the UFC. His has three submissions by Von Flue choke including two back to back wins in 2017.
BJJ and the Von Flue choke
The Von Flue choke is much more rarely seen in BJJ (especially BJJ in the gi). This probably do the fact that top level BJJ competitors are less likely to hold onto guillotines when their opponent has already passed to side control on the other side. The other reason is that the choke seems to be mostly caught from standing positions when people attempt to defend a wrestling takedown with a guillotine.
Polish BJJ blackbelt Adam Wardzinski shows some good tips and variations on the choke in this video.
How to do & mechanics
Get to side control on the opposite side to guillotine attempt
One arm should be as deep as possible under the head.
Other arm goes over their body and if possible traps their guillotine arm