The Activbod team will be visiting bike racks located by roads and railway stations throughout the capital to don bike seats with the specially created plastic coverings, which are designed to keep riders dry on their journey home.
The plastic covers have been specially designed for bicycle seats, however they can also be used in the traditional way, as shower caps. A total of 30,000 covers will be handed out on the day.
Londoners are being invited to tweet @iamactivbod with their postcode and information about the number of bikes at their location in order to receive a visit from the Activbod team.
Activbod is encouraging people to post their #showercapselfie on Twitter or Instagram, tagging @iamactivbod, with the first 100 entries to receive an Activbod product.
Anyone who spots Boris Johnson on his bike and subsequently takes a #showercapselfie as proof will receive the entire Activbod range.
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