The inner and outer tubes are made of high strength aluminum alloy, which is more durable and compact than those plastic ones with smooth surface. The non-slip telescoping pedal and cast iron base make this bike pump more stable, less slippery and less effort when inflating. The rubber tube of the portable pump is removable, freeze-proof and heat-resistant. The high quality seal and flexible tube make it work well in winter and summer. 13.77" L x 5.4" W