Version 4 of the SQWUREL has been improved adding a few valuable features, all packed into the same small form factor of the Sqwurel 3. Canyoneers on the lighter side will appreciate the modified throat geometry that now offers smooth rappeling during double rope rappels (even those of us who are not so small, or light will have a much-improved double rope experience with version 4). The carabiner hole has been enlarged slightly to accommodate larger carabiners while at the same time the groove that holds the O-ring has been made tighter, so the O-ring now grabs the carabiner a little tighter than it used to (a little bit of the best of both worlds here). The behemoth tab has been extended to offer a more secure hold of the rope while also adding a progress capture option to tighten guided rappel lines. Also added are 4 wrenches of 11mm, 12mm, 13mm and 14mm that will fit most rapid sizes you will find in canyon. The rapid wrenches allow tightening and loosening stubborn rapids that are too tight for bare hands.