The invention relates to a fiberglass spool comprising a self-supporting roll (12) having layers of windings (20) located one above the other of an optical fiber (13) for transmitting data that may be unwound from the interior of the roll outwards, wherein the windings (20) are fixed to one another by means of an adhesive bonding agent. In order to realize a sufficiently stable, self-supporting roll (12) that may be reliably unwound from the inside outwards without loops being pulled out of the roll (12), the roll (12) is structured as a cross-winding and a hydrocarbon-based, salt water-resistant, chemically inert impregnating material that may be liquefied by heating is used as the bonding agent.