JQuery :: How To Select From Two Rows Of Checkboxes

I have two different rows of checkboxes. When I do an onclick function I only wish to check one column of checkboxes. Not all of them. The one I wish to edit has Id's of "CBOX01, CBOX02, CBOX03 etc, etc. How can I tell my onclick function to only check the ones with the Id's of "CBOX". I cant get the syntax structure correct.

Here is my code example
$("#CntrHistory").click(function(){
var size = $("input:checkbox[]:checked").size();
if (size == "0") {
alert("One Checkbox Must Be Selected.");
return "false";
} if (size != "1") {
alert("Only One Checkbox Can Be Selected At A Time.");
return "false";
} $("input:checkbox:checked").each(function() {
var str = $(this).val();
var substr = str.split("!");
var comp = substr[0];
var ordr = substr[1];
var eqpt = substr[2];