Pues es ya van por el 19, la verdad a mi parecer parecen unas mancuernas de Fittnes.
Aqui os dejo un par de links:


http://www.ebay.es/itm/UDT-V19-Mechanical-Mod-/261524073811
http://www.vapercompany.com/Youde-UDT-V19-mechanical-mod-p/b6v19.htm
This is a affordable high quality mechanical mod from Youde UD, with stainless steel body, silver plated copper pin, butter smooth threading
and 510 thread connection.
Additional features such as adjustable floating pin which you can flash mount any 510 thread tanks, and top cap has been cut with 3 channels for airflow.
Turn clockwise to unlock botton, and anti clockwise to lock button.
From Youde's test result, this mechanical has almost no voltage drop.
Size: Dia max 25mm, min 21.6mm, H 106mm
Battery size: 18650 only
Material: Stainless steel and copper
Package included:
1 x UDT-V19 Mechanical Mod
1 x Extra bottom contact plate
1 x Extra Screw
Aqui os dejo un par de links:



http://www.ebay.es/itm/UDT-V19-Mechanical-Mod-/261524073811
http://www.vapercompany.com/Youde-UDT-V19-mechanical-mod-p/b6v19.htm
This is a affordable high quality mechanical mod from Youde UD, with stainless steel body, silver plated copper pin, butter smooth threading
and 510 thread connection.
Additional features such as adjustable floating pin which you can flash mount any 510 thread tanks, and top cap has been cut with 3 channels for airflow.
Turn clockwise to unlock botton, and anti clockwise to lock button.
From Youde's test result, this mechanical has almost no voltage drop.
Size: Dia max 25mm, min 21.6mm, H 106mm
Battery size: 18650 only
Material: Stainless steel and copper
Package included:
1 x UDT-V19 Mechanical Mod
1 x Extra bottom contact plate
1 x Extra Screw