Description is wrong for this listing it says its an alt base but that is the 65% I believe it is the CTRL.
Edit: Just did the math and both of the listings are actually not worth it at all, at current prices the TKL version buying all of the parts separately (Switches 50, Keycaps 99, Base 129) it totals to $278, less than the price of this prebuilt. For the 65% it is $10 cheaper.