The CJRB Frack J1931FST is a full-size tactical folding knife built around a 3.9" stonewashed AR-RPM9 drop point blade and a skeletonized frag-pattern stainless steel handle. CJRB set out to make the Frack long, light and powerful, and the weight-relieved full-steel scales are the result — a big pocket knife that still balances and carries well.
An oversized button lock drives fast, confident one-hand deployment, running on a ceramic ball bearing pivot, with a full-size finger choil and a teardrop thumb hole for grip and opening leverage. If you are shopping EDC folding knives, button lock pocket knives, or an AR-RPM9 pocket knife, the CJRB Frack J1931FST covers all three.
CJRB Frack J1931FST – Specifications
| Blade Length |
3.9" (99 mm) |
| Blade Thickness |
0.13" (3.2 mm) |
| Blade Steel |
AR-RPM9 powder steel, HRC 59–61 |
| Blade Finish |
Stonewashed |
| Blade Style |
Drop point, flat grind |
| Handle Material |
Stainless steel, frag pattern |
| Lock Type |
Button lock |
| Pivot |
Ceramic ball bearing |
| Pocket Clip |
Steel |
| Closed Length |
5" (127 mm) |
| Overall Length |
8.9" (226 mm) |
| Weight |
5.04 oz (143 g) |
CJRB Frack J1931FST – Frequently Asked Questions
How long is the blade on the CJRB Frack J1931FST?
The CJRB Frack J1931FST has a 3.9" (99 mm) blade with a 0.13" (3.2 mm) spine thickness, and measures 8.9" overall when open and 5" closed.
What steel is the CJRB Frack J1931FST made from?
The CJRB Frack J1931FST uses AR-RPM9, CJRB's own powder metallurgy stainless steel, heat treated to HRC 59–61. It is a fine-grained steel that takes a keen edge and resists corrosion well, which makes it a strong value pick at this price point.
Is AR-RPM9 good knife steel?
AR-RPM9 is a powdered stainless steel developed in-house by CJRB and Artisan Cutlery. Its powder metallurgy structure gives it finer, more even carbides than conventional budget steels, so the CJRB Frack J1931FST holds an edge noticeably longer than a typical 8Cr or 440-series blade while staying easy to resharpen.
What is a drop point blade?
A drop point has a spine that curves gently down to the tip, creating a broad belly and a strong, controllable point. On the CJRB Frack J1931FST that shape makes it a versatile all-round cutter for EDC chores, food prep and outdoor tasks.
How do you close the CJRB Frack J1931FST?
Press and hold the oversized button on the handle of the CJRB Frack J1931FST, then swing the blade closed and release the button. Keep your fingers clear of the blade path while it swings, and let the ceramic bearings do the work rather than forcing it.
How do you sharpen the CJRB Frack J1931FST?
Match the existing flat grind angle — roughly 18–20 degrees per side — on a diamond or ceramic stone, then finish with a few light strops. Because AR-RPM9 is a stainless powder steel, the CJRB Frack J1931FST responds well to diamond abrasives and needs very little pressure.
Is the CJRB Frack J1931FST a good EDC knife?
It is a large EDC folder. At 5.04 oz and 5" closed, the CJRB Frack J1931FST carries best on the deep-ish steel clip in a jeans or work-pant pocket, and it suits anyone who wants a full-size blade rather than a lightweight slicer. Always check your local blade length and carry laws before carrying it.
Where can I buy the CJRB Frack J1931FST?
You can buy the CJRB Frack J1931FST at Going Gear, an authorized CJRB dealer. Every knife ships brand new with the full manufacturer warranty.
