They are all expandable with several straps to mount to the top tube

Each jockey wheel kit includes:

Requires 3 AAA batteries NOT INCLUDED

Direct mount available for SRAM shifters

Directional - install with the logos out

Spank Spike Vibrocore 350 Rim - Black - Green - 32 Hole - 27.5 Inch netsuite-webdata-created They are all expandable withThe revolutionary Spank Spike 350 rims are here. Utilising a foam filled rim to dampen vibrations, Spank has successfully brought their Vibrocore technology from their handlebars into rims, and the results are impressive. Not only does the vibrocore dampen the ride of the bike, it also increases torsional strength and lateral stiffness. Featuring Spank's bead bite rim technology to minimise the chance of the tyre burping and also increase tubeless