Nockturnal Lighted Nocks Size Chart

In the pursuit of the perfect shot, visibility is everything. Whether you are tracking a trophy whitetail through the timber at dusk or analyzing your arrow flight on a long-range target, Nockturnal Lighted Nocks have become the industry gold standard for reliability. However, with the explosion of arrow technology—ranging from ultra-micro shafts to heavy-duty crossbow bolts—the most common question archers ask is: “Which size fits my arrow?”

Nockturnal Official Size Chart

Nockturnal utilizes a letter-coded system to identify their sizes. Below is the comprehensive breakdown of the internal diameters (I.D.) each letter represents and the most popular arrow shafts they fit.

Size Code	Internal Diameter (I.D.)	Fits Popular Arrow Shafts
G	.165″ / .166″	Easton Deep Six, Victory VAP, Black Eagle X-Impact
X	.204″	Easton Axis, Victory RIP, Black Eagle Rampage, Gold Tip Kinetic
H	.231″	Easton Hexx, Easton Hyperspeed, Beman ICS Hunter
GT	.246″	Gold Tip (Standard), Victory VForce, Black Eagle Outlaw
S	.244″	Easton 6.5 Matrix, Carbon Express Maxima, Beman ICS
Fit	Universal	Includes bushings to fit X, H, S, and GT diameters

1. The “G” Nock (The Micro-Diameter)

The “G” size is designed for the modern “ultra-micro” movement. These arrows (.165″–.166″ I.D.) are built for maximum penetration and minimum wind drift. Because the walls of these shafts are so thin, the G-size Nockturnal is incredibly slender. If you are a backcountry hunter using Victory VAPs or Easton Deep Six shafts, this is your dedicated size.

2. The “X” Nock (The 5mm Standard)

For years, the .204″ I.D. (often called 5mm or “X-diameter”) has been the “sweet spot” for bowhunters. The Nockturnal X-size is engineered for shafts like the legendary Easton Axis. This size provides the perfect balance between the durability of a standard shaft and the penetration of a micro-shaft.

3. The “S” vs. “GT” Confusion

This is the area where most archers make mistakes. Both the S and GT sizes fall into the “Standard Diameter” category, but they are not the same.

• S-Size (.244″): Fits most Easton 6.5mm and Carbon Express shafts.
• GT-Size (.246″): Specifically designed for the slightly wider internal diameter of Gold Tip arrows and Victory VForce. While you can sometimes force an S-nock into a GT shaft, it will be loose and potentially fail. Always match the .002″ difference correctly.

The Nockturnal “Fit” Series: The Ultimate Solution

If you switch arrow brands frequently, Nockturnal introduced the “Fit” Series. This is a universal lighted nock system that comes with a set of interchangeable sleeves (bushings). By sliding the correct sleeve onto the nock base, you can convert a single nock to fit X, H, S, or GT shafts. This is an excellent option for shops or archers who keep multiple sets of arrows in their quiver.

Weight and Balance Considerations

When adding a Nockturnal to your arrow, you are adding weight to the rear of the shaft. A standard plastic nock usually weighs about 8–12 grains, while a Nockturnal weighs approximately 20–25 grains depending on the size.

Component	Weight	Impact on Arrow
Standard Nock	~10 gr	Baseline flight
Nockturnal (G/X)	~21 gr	Slight FOC decrease
Nockturnal (S/GT)	~25 gr	Moderate FOC decrease

Adding ~15 grains to the back of the arrow will slightly shift your Front-of-Center (FOC) toward the rear. For most hunters inside 40 yards, this change is negligible. However, if you are a long-range shooter (60+ yards), you should practice with your Nockturnals to ensure your point of impact hasn’t dropped slightly compared to your practice nocks.

Final Maintenance Tips

To get the most out of your Nockturnals, remember that the batteries are not replaceable. To preserve life:

• Reset Immediately: Use a small tool (like a broadhead tip or a small screwdriver) to slide the activation switch back up to the “off” position immediately after recovery.
• Storage: Store them in a cool, dry place. Extreme heat can drain the lithium batteries over the off-season.
• Check the Fit: If the nock “clicks” too easily or feels “mushy” when seating, inspect the end of your carbon shaft for tiny hairline cracks.

Choosing the right Nockturnal size is the simplest way to upgrade your hunting setup for 2026. By matching your internal diameter to the chart above, you’ll ensure that when the moment of truth arrives, your arrow’s path is as clear as day.