Internal Retaining Ring Circlip Pliers, Bent Jaw

Some retaining rings cannot be reached from a straight-on angle. The ring sits at the bottom of a stepped bore, or inside an offset cartridge subassembly, or behind a face that blocks the straight-jaw tool from entering. The 538PLUS/1DP-US is the bent-jaw answer; the jaw tips angle off the handle plane so the pliers can reach around an obstruction and still engage the ring's hole pattern.

The bent geometry sacrifices nothing on jaw-tip sharpness or holding force; it just changes the angle of approach. For a workshop that already owns the straight-jaw 536 internal pliers, the 538 is the second-tool answer that turns "we can't reach the ring" into "we can." For a workshop building up the circlip kit from scratch, the bent-jaw version is often the more useful first purchase; it covers both straight-on and offset access, where the straight-jaw tool covers only the easy case.

What we use it for, in the shop

• Internal rings inside damper-cartridge subassemblies where the cartridge body blocks straight-on access.
• Internal rings at the bottom of stepped bores where the straight-jaw tool would not engage cleanly.
• Internal rings inside air-spring negative chambers where the access angle is constrained by the surrounding casting.
• Any internal ring where the straight-jaw 536 cannot reach the engagement holes.

Specs

• Jaw geometry: bent, internal (jaws close on squeeze, compressing the ring)
• Bend angle: angled off handle plane for offset access
• Material: premium plus carbon steel, drop-forged
• Heat treatment: hardened and tempered
• Finish: trivalent chrome plated to ISO 1456:2009
• Article: 538PLUS/1DP-US

Built in Zreče, Slovenia

Unior has been forging hand tools in Zreče since 1919, and is the official technical partner of multiple World Tour and downhill teams. Bent-jaw geometry for the angles the straight tool cannot reach. Same drop-forged premium plus carbon steel construction, same jaw-tip sharpness, same retention force; the only difference is the access angle the geometry buys back.

Pro tip from our mechanics

Some damper bodies live at angles the straight-jaw circlip pliers cannot reach; the cartridge sits inside a casting that blocks the direct-on approach, and the only way to engage the internal ring is with the bend. The 538 is the procedure variant for those cases. A workshop that does damper service across multiple shock and fork brands owns both pliers; the bent version is the one that turns the harder jobs into the same bench job as the easy ones.

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