The disclosed bladder (10) is useful in ambient temperature fabrication of rubber parts and components. Due to the particular combination of construction materials used, the bladder has excellent release properties and results in improved manufacturing uniformity. At least one portion of the bladder (10) is formed from a lack tack, high abrasion resistant polyurethane. The polyurethane may comprise a ring-shaped portion (26) of the bladder surface or an entire end (20) of the bladder.