An apparatus for closing a wall of a body lumen to deploy a closure element. The apparatus comprises a resettable triggering system which may be slideably moved within a housing to advance a carrier assembly and/or locating assembly, and which deploys the closure element. Upon deployment of a closure element, the carrier assembly may be positioned in a distal position and locked in place within a housing. The lock may be effected by a flexible snap fit interlocking feature which is selectively releasable. Release of the locking feature may be performed by externally insertable tools which engage the flexible snap fit and release the interlocking features. The triggering system may also include a catch which is released upon deployment of a closure element. The catch can be reset to allow the triggering system to be re-engaged into a pre-deployment condition and position.
