It's unique design, featuring the filrer cup and funnel fit offers flexibility to filter water into bottles with a wide range of bottle sizes, including wide & narrow mouth bottles, coomercial water bottles, soft drink bottles, canteens, SIGG & Klean Kanteen bottles, Gatorade and Nalgene bottles.

Features:

• FitsAll filter features a durable 40 x 40 micron screen that removes particulates larger than 40 microns from water while you fill your bottle
• Just as the name implies, the filter fits nearly any size bottle on the market, from generic single-use plastic bottles to name-brand reusable bottles
• Filter also enables the Steripen Journey, Classic and Traveler purifiers (sold separately) to be used with wide-mouth bottles in the inverted position for simple purifying
• Rugged, flexible material allows the filter to stow away compactly and then snap back to shape when unpacked

Specifications:

• Weight: 65 g
• Dimensions: 9 x 9.5 x 7 cm