Size Matters Black Cylinder Sleeve. Get your pump on, comfortably! With the convenience and durability of the Cylinder Comfort Seal from Size Matters, now pumping sessions are more comfortable and enjoyable! Simply slip the stretch to fit comfort seal over your pump and start pumping away. Made to fit over any Size Matters penis pump cylinder and easy to clean. Measurements 2.79 inches external diameter, 0.98 inch internal diameter, 1.41 inches tall. Material Thermoplastic Rubber TPR. Color: Smoke Black. Please note pump cylinder not included, sold separately.