STI KIT-BB0SS Back box for slim/mullion

The STI KIT-BB0SS is a surface-mount back box for STI slim-line and mullion-mount Stopper Stations. It lets a slim Stopper Station push button install on a flat surface where no recessed box exists. Therefore, it is the standard fix for door frames and narrow mullions.

Where the STI KIT-BB0SS fits

Mullion-style buttons are designed for tight spaces, such as aluminum storefront door frames. However, those locations rarely offer a flush electrical box. As a result, this back box provides the mounting depth and wire room the station needs. Distributor listings give a depth of 1.5 inches.

Verified specifications

• Type: Surface-mount back box accessory
• For: STI slim-line / mullion-mount Stopper Station push buttons
• Depth: 1.5 in (per STI distributor listings)
• Brand: Genuine Safety Technology International (STI) OEM accessory

Ordering notes

This is an accessory only; the Stopper Station itself is sold separately. Also, confirm your station is the slim/mullion format before ordering, because full-size Stopper Stations use different back boxes. Finally, our team can verify compatibility against your station’s exact model number.

Need help selecting the right part or verifying compatibility? Our team supports thousands of commercial fire alarm installations every year. Call us at 1-888-557-0558 or email sales@lifesafetycom.com for application guidance, lead-time updates, or volume pricing.