Thanks Toby.
Got some 224's I need to get to y'all.

Toby can u put a D battery on a C collar Kevin

Ya all collars can be upgraded one battery size as long as they never have been up graded before.

btt

Can you upgrade a ultra light to a c

Kale no sorry that can't be done but it can be upgraded to a standard light which is double the hours of a ultra light. Cost to do it would be 35.00 per collar. If you get it here before the end of the month it will cost 31.50