Pull-truded (pulled / extruded) rods are made with all the fibers aligned lengthwise. They are very light, strong in tension and torsion (pulling and sideways deflection) and relatively cheap.

Pulltruded Carbon Fiber Pull-truded Tubes - 36" long
Decimal Size	Inside Diameter		Fractional Size		Metric Size		Weight
.125" * ferrules	.070"		1/8"		3.00 mm		7.6 gr
	$2.50 each - Qty:  ' 12 34 56 78 910				12-Pack $25.00 - Qty: 12 34 56 78 910
.156" ferrules	.098"		5/32"		4.00 mm		10.7 gr
	$2.75 each - Qty:   12 34 56 78 910				12-Pack $27.50 - Qty: 12 34 56 78 910
.180" ferrules	--		--		4.55 mm		-- gr
	$2.85 each - Qty:   12 34 56 78 910				12-Pack $28.50 - Qty: 12 34 56 78 910
.196" ** ferrules	.123"		~13/64"		5.00 mm		17.4 gr
	$3.00 each - Qty:   12 34 56 78 910				12-Pack $30.00 - Qty: 12 34 56 78 910
.220" ferrules	--"		7/32"		5.50 mm		-- gr
	$3.25 each - Qty:   12 34 56 78 910				12-Pack $32.50 - Qty: 12 34 56 78 910
.254"	--"		1/4"		6.50 mm		27.6 gr
	$3.50 each - Qty:   12 34 56 78 910				12-Pack $35.00 - Qty: 12 34 56 78 910
*   .125" tubes are a little curved so that a 36" section can have a bow up to 1/8" (or less).     **   the inside diameter is almost enough, but not quite large enough to fit a .125" rod or tube inside. A little pressure, scraping or sanding will make the ends fit into each but the end of the .196" tube should be wrapped with thread on the outside to keep it from splitting.

Pull-truded tubes are used for reinforcing foamies either as spars or length-wise to stiffen the fuselage. You can also use them to join elevator halves, pushrods, or motor mounts.
Used to for booms on pod-and-boom aircraft, on parkfliers and such where high performance and low weight are trumped by low price and durability. However, on gliders and other planes where the boom fuselage will be longer, and where light weight is more critical a wrapped carbon fiber tube will work much better.

Foam Sheets	Zepron (white - thick, medium, thin)       Depron (white, 3mm)
Carbon Fiber &Composites	Smooth Carbon Tubes     Tube Ferrules     Wrapped Carbon Tubes Round CF Rods     Flat CF Rods     CFF Fittings     Fiberglass Rods Carbon Strips     Carbon Tow     Kevlar Tow     Carbonara
Electrical Stuff	CS Shrink     Flex Shrink     Silicone Wire     Servo Wire JiffyPin Connectors     JST Connectors     Other Connectors
Tools	Carbon Cutter    CS-3 blades   Mini-Tool Sets   Sanding Sticks "Crazy Knife"   Mini Saw Blades   Dial Caliper   Rotary Cutter Compass Cutter   "Mother of All Scissors"   Hold-It's
Stick'ums	Blenderm     CA Glues     Transfer Tape
Other	Prop Adaptors     Du-Bro Parts     Sulivan Parts DraganFlyer / RoswellFlyer Rotors Other PF Stuff     TT Inserts     Lights, Lights, Lights!