Internal Retaining Ring Circlip Pliers

Internal retaining rings sit inside a bore and hold a seal carrier, a bearing race, or a damper-piston seat against an internal shoulder. Removing them is straightforward only if the pliers' jaw geometry matches the ring's hole spacing; and only if the pliers are the kind that spread on squeeze, not the kind that close. The 536PLUS/1DP-US is the straight-jaw internal-ring pliers built for the standard-position access.

The plier's jaw tips drop into the two small holes on the ring's inner face. Squeeze the handles and the jaws move together, compressing the ring inward and freeing it from the groove in the bore. Release the squeeze and the ring snaps back open to its retaining diameter. The action is straightforward and predictable across years of use, provided the jaw tips stay sharp enough to engage the ring's holes without slipping out under load.

What we use it for, in the shop

• Internal-ring retention on damper-piston seats during damper-cartridge service.
• Internal-ring retention on bearing races inside hub bodies and bottom-bracket cups.
• Internal-ring retention on seal carriers inside air-spring assemblies.
• Any internal retaining ring where the ring is accessed from a straight-on direction.

The straight-jaw geometry is the workshop default. Reach for the bent-jaw version 538PLUS/1DP-US when the ring sits at an angle the straight tool cannot reach.

Specs

• Jaw geometry: straight, internal (jaws close on squeeze, compressing the ring)
• Material: premium plus carbon steel, drop-forged
• Heat treatment: hardened and tempered
• Finish: trivalent chrome plated to ISO 1456:2009
• Article: 536PLUS/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. Straight-jaw geometry for internal rings; the standard workshop position, where the ring is accessible from a direct angle and the bent variants are not needed. The drop-forged premium plus carbon steel construction is what keeps the jaws sharp across years of seal-carrier and damper-piston service.

Pro tip from our mechanics

Damper-cartridge service goes deeper than the home lower-leg interval. The circlip pliers are the next step into damper internals if you choose to take it; internal retaining rings hold the damper-piston seat against the cartridge wall, and there is no other way to remove them without the right tool. For the home interval, a lower-leg service does not need this tool; for the deeper-than-home interval, this is one of the first tools the procedure calls for.

How to service your suspension fork's lower legs →