Quick release battery terminal with fused bypass and red knob  Ref: CLS1016

Battery post master switch shown dis-assembled. For long term storage you could separate the two halves completely (although not necessary), as shown here. Short term you just slacken the red or green knob. To maintain radio codes, alarm etc. an inline fuse needs to bridge the two sections. Preferably you should wire the radio and alarm directly to the battery via an inline fuse such as CLF051.