Just telling a guy with an old style recurve @ work 2day that there's a Chinese brand that makes alot of great trad gear for the $ called Fivics. 😀 Those slots in the limb pockets is what the spring loaded ILF buttons on every set of ILF limbs slides into & then the limb bolts holds the limb in place under tension. It's important to hold the riser by the grip & have both the string & the bow stringer attached to the limbs. What's nice about ILF is that u can have different sets of limbs with a string attached to each set. Only need one riser & everything was u tune it is all tuned everytime u put it on your one riser. 😅