Easton 4mm G Nocks Groove Blue Small. The 4mm G Nock is compatible with the Inspire carbon arrow as with the Super Drive Series with the Corresponding Super Drive 4mm bushing. Specifications for Easton 4mm G Nocks Groove: Manufacturer: Easton Additional Features: F/G Nock Features of Easton 4mm G Nocks: Available in multiple colors Large groove 12 pack 7 grains Package Contents: Easton 4mm G Nocks Easton 931455: 4mm G Nocks Groove Blue Small