It is one of the few removable appliances made for distalization of molars and thus require patient compliance for the treatment to be successful.
[1][2] In this appliance, the fingers springs are the main component which act against the 1st molars to move them distally.
The original appliance developed by Margolis included helices next to the laterals and canines for a straight pull or Northwest headgear tubes to be inserted.
[4] Dietz et al. recommended that to avoid tipping of molar teeth, a high pull headgear can be used in conjunction with this appliance.
In order to avoid loss of anchorage, they also recommended to achieve "overcorrection" of the molar distalization by 2mm or more.