Two pushbutton (aka QD or snap-in) sling swivel attachments arrived Using the SR-15E3 and there are ambidextrous holes to snap them into within the SOPMOD buttstock and at 3 areas on all sides of your upper and reduced receivers.Experienced to tug the set off on this upper – u only Reside at the time .. This can be my 2nd KAC upper from RooftopDe