All LiPo battery packs must ship either UPS ground or USPS Parcel Select. NO EXCEPTIONS! Using any other service will delay shipment.
LiPo packs is the 'steam' which pushes the power to the 'heart' (motor) of your race car! And I take great care in the sourcing and testing these packs under race conditions.
Finding quality companies to produce 'race cells' for packs has been difficult, and have a great partner company who knows what is needed. Quality construction is the key!
Unlike other companies, I test the packs before they are sold to justify them being called a race pack!