You can count on it being a frame (6)
I believe the answer is:
abacus
I believe this is a double definition.
'you can count on it' is the first definition.
(an abacus is a tool for doing sums)
'a frame' is the second definition.
(I have seen 'frame of sorts' mean 'abacus' so perhaps 'frame' could also mean 'abacus')
'being' acts as a link.
(Other definitions for abacus that I've seen before include "Basic calculator makes" , "frame of sorts" , "It might work out" , "Calculating frame" , "Counting-bead device" .)