SKU PSM0521UB Category

Pitstopper Allen Head Plugs

(2 customer reviews)


An exceedingly simple, yet effective way to protect the ancillary components of your bike from opportunistic thieves. Protect any item on your bike that uses an allen bolt with Pitlock Pitstoppers.

Pitstoppers come in four sizes: M5, M6, M8, and M10.

Learn more about Pitstoppers, how to install them, and why they work by checking out our guide to Pitstoppers.

See below for additional product and sizing specifications.



Pitstopper plugs appear to be cylindrical when in fact, they have an extremely minute conical shape. Push the plug a few millimeters into any allen socket of the corresponding size, tap in with a hammer, and you’re finished.

To remove, thread the included screw into the Pitstopper plug and tighten until the plug is popped out by the screw bottoming out in the allen head. Pitstopper use a non-standard thread and pitch, and are very difficult to remove without the screw that came with your set. Do not lose this! A detailed installation video can be found on our Pitstopper guide page.


The designation of M5/M6/M8/M10 refer to the diameter of the bolt threads, not the size of the allen wrench. The wrench for any particular allen bolt is smaller than the bolt diameter.

M5 = 5mm thread diameter and uses a 4mm allen wrench
M6 = 6mm thread diameter and uses a 5mm allen wrench
M8 = 8mm thread diameter and uses a 6mm allen wrench
M10 = 10mm thread diameter and uses an 8mm allen wrench

Additional information

Pitstopper Size

M5, M6, M8, M10

2 reviews for Pitstopper Allen Head Plugs

  1. Mark W. (verified owner)

    I used this to protect Allen screws attaching my saddle to the seat post. An alternative is to find a ball bearing and glue it in place. But the glue method means you can’t adjust the Allen screw during a ride – at best you have to dissolve the glue at home. This is a simple solution, and can be used to protect other items like brakes.

  2. John M DeMarco (verified owner)

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