Vulcanized uncured flashing EPDM rubber stretches and conformns to the areas applied and is meant for flashing vents, penetrations, corners and ventilation units. Primer must be used with this product in order for the liners and the tape to vulcanize (adhere) together. (Primer NOT included).(1) 6" x 25' vulcanized EPDM butyl flashing tape used to seal "flash" around roof top detail projections overlapping pieces of EPDM deck sheet roofing to form a watertight seal.You must use primer activator to prime the seam area before applying the 6" flashing tape.Peel and stick installationStong butyl based tape pefroms well under hot and cold conditions