I use the disposal ones that come in two packs.  They sell them at CVS.  You open the package and shake the bag to activate them.  They produce heat for up to 10 hours.  I put them in my gloves-tried them on the backs of my hands in gloves but fingers still got cold.  I put them in the palms of my hands inside loose gloves.  They work ok.  I can shoot with them in place. 

I use the jonee warmers and white gas.

4 hours ago, norton said:

I use the disposal ones that come in two packs.  They sell them at CVS.  You open the package and shake the bag to activate them.  They produce heat for up to 10 hours.  I put them in my gloves-tried them on the backs of my hands in gloves but fingers still got cold.  I put them in the palms of my hands inside loose gloves.  They work ok.  I can shoot with them in place. 

I buy a case of these each Fall and throw them into the trunk of the car.  In the Spring I throw them away.  MN Winters aren't to be fooled with.