After being on the ice with other anglers, I'm glad I went the route of a fishfinder like mine that has the built in flasher option. This way I can use it all year round and the flasher is VERY sensitive (if I want it to be). I went out fishing last week and forgot the sonar. Didn't get one fish. Why? It's not that I can't catch fish without it, but this lake you HAVE to entice them to bite. Very rarely will they strike right off the bottom. This way I know if there is a fish around to even entice.