5/16″ OD, 9/64″ ID Fiberglass Round Tube


Pultruded Fiberglass Tube

Nominal Dimensions
Outer Diameter: 5/16″
Inner Diameter: 9/64″
Color: Black

Length: Choose the length of the tube

SKU: RT-516-964 Categories: , , Tag:

5/16″ OD, 9/64″ ID, Fiberglass Round Tube, Black

Our 5/16″ OD, 9/64″ ID, fiberglass tube is made by the pultrusion process. Fiberglass unidirectional roving (for maximum strength), pulled via hydraulics through a bath of resin and pigment. Heated and cured. Our stock lengths are the perfect sizes to ship via standard parcel carriers like FedEx and Post. 8 foot long lengths fit under the oversize 3 shipping mark. Oversize 3 goods (anything over 96.02 inches) will all ship at freight rates which start at $120 and rise from there making our lengths of tube perfect for prototyping, hobbyist, etc…

This listing contains all of the product offerings for the 5/16″ OD, 9/64″ ID Round Tube including: RT-516-964-05, RT-516-964-2, RT-516-964-4, and RT-516-964-8

Round Small Tube Typical Properties

Round Small Tube Properties

MGS Fiberglass Sizes that sleeve 5/16″ OD, 9/64″ ID, Round Hollow Tube:

RT-516-964 .3125 inch Round Hollow Tube sleeving RSR-18 .125 inch OD Round Solid Rod diagram - Max-Gain Systems, Inc.
1/8 inch OD (.125″) Round Solid Rod fits inside our 5/16 inch OD Round Hollow Tube (full length sleevable)

Attachments that fit-on, clamp-on, couple, etc…

FER-ALUM-516 5/16 inch Aluminum Ferrule

The 5/16 inch Aluminum Ferrules fit on the end of the 5/16 inch OD Round Solid Rod and 3/8 inch OD Round Hollow Tubes and allows the connecting of two rods or tubes

5 16 inch Round Tube and Rod Snap Spring Clip MGS-CLP-00-516 800x800 - Max-Gain Systems Inc

The 5/16 inch Tube and Rod Storage Clip accepts our 5/16 inch Solid and holds it with a snug grasp. Multiple may be needed for long items.

Vinyl End Caps 800x800 - Max-Gain Systems, Inc.The 5/16 inch Vinyl End Cap fits on the end of the 5/16 inch OD Round Tube.

Data Points for using 5/16 inch OD (.3125″) Round Hollow Tube

RT-516-964 .3125 inch OD Round Hollow Tube can take 10 AWG Bare Solid Wire or 12 AWG Bare Tightly Wound Stranded Wire - Max-Gain Systems, Inc.


Our 5/16 inch OD (.3125″) Round Hollow Tube can accept 10 AWG (gauge) Bare Solid Wire or 12 AWG (gauge) Bare, Tightly Wound, Stranded Wire.

Round Tube Sleeving and Reinforcement

Sleeving and Reinforcement Guide Round Tube and Rod 800x800 - Max-Gain Systems, Inc.

Round Tube Sleeving Sample Pack

RT-SPL 250x250 Fiberglass Round Hollow Tube Sleeving Sample Pack - Max-Gain Systems, Inc.

This Round Tube is available in a Round Sleeving Tube Sample Pack for easier product evaluation. Easily acquire a 6 inch or 2 foot long piece of each size of Round Fiberglass Tube.

Please note: The sleeving and reinforcement guide below is for Max-Gain Systems’ proprietary line of tube and rod only. All sizes are “nominal” and allow a few thousandths for sleeving purposes.

These same stated sizes of tube and rod from other manufacturers probably will NOT mate with our line!

Round Tube
Tubing Size
Accepted Inside Sizes
Accepted Outside Sizes
no direct sizes
no direct sizes
no direct sizes
no direct sizes
no direct sizes

Fiberglass Information and Resources


Fiberglass Joining 250x250 - Max-Gain Systems, Inc.

Joining and connecting tubes and rods together through many different methods. Find out which method works for you!


FG Circular Saw Raw 250x250 - Max-Gain Systems, Inc.

Information on cutting and drilling fiberglass tube and rods. Including which tools work best!


Bonding & Adhesives 250x250 - Max-Gain Systems, Inc.

Information on bonding fiberglass shapes together thru chemical adhesion. Including what NOT to use!


Painting Fiberglass with Rustoleum Spray 250x250 - Max-Gain Systems, Inc.

Information on painting fiberglass tube and rods. Best practices and tips on how to make it less visible.


Fiberglass Quad Spreaders and other sleeved fiberglass 250x250 - Max-Gain Systems, Inc.

We offer telescoping, Quad Spreaders with usable lengths up to a total of 26 feet! Telescoping Quad Spreaders are discounted from individual piece prices! See our Quad Spreader Information Sheet for details.


Quantity discounts on fiberglass preformed shapes 250x250 - Max-Gain Systems, Inc.

Buying ten or more quantity of one size of fiberglass qualifies for a 10% quantity discount on that item. Fifty or more, of one size, qualifies for 15%, and one hundred or more 20%.


Manufacturing pultruded fiberglass tube and rod 250x250 - Max-Gain Systems, Inc.

If you are a reseller or manufacturer, you may qualify for our factory-direct, wholesale/O.E.M. pricing! SUBSTANTIAL savings are possible with increasing volume, and our customer service is unsurpassed. Email us for quantity pricing.


Drilling3 grayscale 250x250 - Max-Gain Systems, Inc.

Available free by telephone. For almost unlimited life, we highly recommend that any fiberglass – even ours which is UV-stabilized – be painted. A sprayed primer coat and flat-black top coat, works best. (See our Max-Tips Info Sheet for details.)

About Max-Gain Systems, Inc.

Max-Gain Systems, Inc. carries a full line of in-series, between series, right angle, T-shaped, quick connect, handie-talkie (BLACK), pigtails (coaxial jumpers), etc… RF adapters. Our RF adapter lines are constantly expanding. We keep our RF connector and adapter lines in stock. We ship both retail and wholesale quantities. To become a dealer / wholesale user, contact us with your potential usage.

Max-Gain Systems, Inc. is the number one supplier of fiberglass round hollow tube, square tube and round solid rod to the antenna manufacturing industry. We produce millions of feet a year for hundreds of different industries. Including but not limited to: marine / boating, aeronautical, agriculture, construction, emergency services, etc…. We have the unique ability to sell one piece or even a semi-truck full. Feel free to prototype using our fiberglass tube and rod then contact us for a quote on a production run. At production run quantities we can cut to your desired lengths at no additional charge. We can also perform several different fabrications (example: drilling holes in precise locations along a tube) to ensure your delivered material is ready for assembly. We have several accessory items designed for our fiberglass including but not limited to: couplers, telescoping clamps, ferrules, etc…

RT-516-964-05, RT-516-964-2, RT-516-964-4, RT-516-964-8

Additional information

Shipping Weight N/A
Shipping Dimensions N/A
Outer Diameter

5/16" OD (.3125 in) | 7.93 mm

Inner Diameter

9/64" ID (.141 in) | 3.57 mm

Wall Thickness

3/32" Wall


6 in, 23.25 in, 46.5 in, 93 in




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