What this is
The CM40 is Bessey’s Light-Duty (CM) drop-forged C-clamp line, at 4" capacity — a smaller, more affordable option than the Heavy-Service B-HS8 covered in our C-clamps comparison. It shows up frequently in “most bought” C-clamp listings, likely because 4" light-duty clamps cover more general small-job holding than an 8" heavy-service clamp most home shops don’t need.
Full specs
| Spec | Value |
|---|---|
| Model | CM40 |
| Clamping capacity | 4" |
| Throat depth | 3-1/4" |
| Clamping force | 1,200–1,300 lb — retailer listings disagree on the exact figure |
| Weight | Not confirmed — only found in one unclear source, not repeating it here |
| Material | Drop-forged steel frame, black powder coat; swivel pad; cold-drawn steel spindle; steel sliding T-bar |
| ASIN | B0006694IC |
Source: cross-referenced retailer listings (Home Depot’s product title and Industrial Tool Crib both independently list a 3-1/4" throat depth, which we’re treating as confirmed since two independent sources agree). The clamping force figure is inconsistent between sources (1,200 lb vs 1,300 lb) — we’re presenting both rather than picking one. Bessey’s own site didn’t have a directly fetchable spec page for this specific model at the time we checked.
Bessey CM40 Drop Forged C-Clamp (4")
Bessey's Light-Duty (CM) line, not the same product as the Heavy-Service B-HS8 covered in our C-clamps comparison — smaller capacity, lighter build, lower price point.
View Price on AmazonWho this is for
Small parts, jig assembly, model-making, light metalworking — jobs where a compact 4" clamp with real drop-forged construction (not stamped sheet metal) is enough, and you don’t need the 8"+ reach or heavier-duty rating of the B-HS8.
Who this isn’t for
If you need real reach into a workpiece or a rated force in the thousands of pounds for genuinely heavy holding, this is undersized — see the Bessey B-HS8 (8", 27.5 lb) in our C-clamps comparison instead.
Bottom line
This is a retailer-cross-referenced spec writeup, not a hands-on test — we haven’t physically clamped anything with this unit. On paper it’s a compact, genuinely drop-forged (not stamped) light-duty C-clamp, with one unresolved discrepancy in the published force rating that we’re flagging rather than papering over. Bessey CM40 if 4" capacity covers your work.