Was just browsing the store and found this.
From the site:
FREE Summit Club Membership from Thu 30 April to Mon 8 June 2020
Add to your shopping cart now, then resume shopping. Summit Club prices applied instantly.
Membership discounted to FREE at checkout.
It's also worth noting that there is 40% off all Kathmandu branded items for members, so if you add the membership you will also get the 40% off!
Thanks to delirium211 for confirming you must make a purchase.