In general, endorsements are used to expand or restrict coverage for certain types of loss. For example, a sewer backup endorsement adds coverage for losses caused by sewer backups to a policy that otherwise wouldn’t cover them. Meanwhile, riders and floaters are used to add certain types of property to the policy. For example, a jewellery rider adds coverage for individual pieces of jewellery that might not have enough coverage under the standard policy. Or, a watercraft floater would add coverage for individual boats.