z fins slalom sf small formulaDelivery times: Unfortunately, all custom Fins have extended delivery times due to production bottlenecks. We are in direct contact with the manufacturer and can therefore guarantee the fastest possible delivery. However, in some cases, delivery may take up to 1 4 months. Introducing the Slalom SF fin. SF is like a small Formula fin that fits well with slalom boards. The SF is made for 8 course slalom and marathons where you need extra performance