Thicker and More Malleable
3M Short Strand Reinforced Filler is thicker than regular filler, so it requires a bit more effort to mix. Compared to long strand fiberglass filler, short strand filler is also a bit more malleable and softer. Fiberglass filler is great for applying over welded areas and can be used as a build layer where thicker applications of body filler are needed.
A Unique Line of Reinforced Filler Products from 3M
Altogether, the 3M line of reinforced filler products offer users a unique and flexible array of repair solutions. Each product is reinforced with short fiberglass strands, long fiberglass strands or milled fiberglass. These reinforced fillers are significantly stronger than regular fillers and are waterproof. They are great for repairing fiberglass and rust holes in metal.

Dynabrade 51989 Collar
Dynabrade 52580 4" (102 mm) Dia. Straight-Line 6" (152 mm) Extension Cut-Off Wheel Tool, Rear Exhaust, 1 HP, 18,000 RPM, 3/8"-24 Spindle
Dynabrade 33195 NDDP2005, Left Hand Clamp Lever
Dynabrade 11462 Dynabelter Finisher
Dynabrade 78546 1-1/4"Dia. 2-Set, 8-32 Female Center Thread, 80 Grit, Dynacut A/O Overlap Slotted Disc, 100/pack
Dynabrade 77775 5" Dia. x 7/8" Center Hole, 120 Grit, Type 27, Ceramic DynaCut Flap Disc, 10/pack
Dynabrade 94851 12' Max Flow 5/16" I.D. Air Hose Assembly, Male (1/4") / Male (1/4") Fitting Ends Included
Dynabrade 40378 Rubber Drive Wheel, Mini Dynafile II
Dynabrade 54421 3" Dia. Right Angle Disc Sander, Steel Housing, Rear Exhaust, .7 HP, 18,000 RPM, 3/8"-24 Thread
Dynabrade 78750 1" x 1"-A25 DynaFire A/O Mounted Point, Vitrified, 5/pack
Dynabrade 48535 3" Dia. Epic Finish Kit With 48531 Geared Disc Sander, Rear Exhaust, .4 HP, 15,000 RPM 
