Thanks. Forgive me, however, as I am a bit confused.
Are you both stating that the servo horn on my Hyper 7 should fit onto the splines of the Airtronics servo? The problem appears that the servo horn "hole" (not sure what it's called) is a bit smaller than the splines, so it does appear to fit. Honestly, I did not force the horn down all too strongly on the servo, but can try again.
Or...are you saying I need the adapters (
http://www.amainhobbies.com/product_info.php/cPath/1_25_1461_635/products_id/13634/n/OFNA-Servo-Horn-Heavy-Duty-Blackm )
Thanks!