Family Tent: A tent which is large enough to shelter an average-size family.
Fibre: The thin strands that are bundled or twisted together to form a yarn.
Figure 8: Metal abseiling/belaying device shaped like an 8.
Fill: A term to describe the contents of an insulated product. E.g. Down, Synthetic etc.
Fill power: A measure of how much space (in cubic inches) a sample quantity of down will occupy. The higher the fill power, the more still air the down traps, and the greater the insulation it offers will be. American and European methods for measuring fill power do not give the same measurements (the American method gives a higher measure).
Fill Weight: Tells you how much down is in a sleeping bag. To accurately gauge an insulated products performance this figure must be used with fill power.
Fleece: A knitted synthetic fabric which is brushed on both sides to give a soft ‘fluffy’ pile finish.
Fly Sheet: A water-resistant, removable tent cover, which is spaced above and away from the tent to protect against wind, rain, and condensation.
Footbeds: The part of the sole that your foot lies directly upon. Often removable, the footbed is contoured and provides foot positioning, comfort, and insulation. Aftermarket footbeds can improve boot fit and upgrade performance.
Full-Grain Leather: Leather made from the full thickness of the animals hide.