The Wera 3950 PKL in 4mm is one of the most commonly specified sizes in the range, ideal for M5 socket head cap screws used extensively in general engineering, machinery maintenance, and structural assembly applications. Constructed from high-grade stainless steel, this key prevents the transfer of extraneous rust to stainless fixings — a key benefit in corrosion-sensitive industries. The Hex-Plus profile delivers a larger contact surface inside the screw head, substantially reducing notching an
The only currently-tracked offer for this product.
| Merchant | Price | Shipping | Total | Rating |
|---|
| Tooled Up· new | £5.49 | £5.95 | £11.44 | — |
Price shown as reported by the merchant — final price is confirmed at checkout. See Affiliate Disclosure.
