Sargent NB-8710-F Top Latch Surface Vertical Rod Exit Device - Exit Only - 36"

The Sargent NB-8710-F is a surface vertical rod exit device from the Sargent 8700 series-specifically the less bottom rod version, configured for exit only function, with a 36-inch rail for doors 33 to 36 inches wide. If you've been searching "sargent 8710" and you're trying to decide between the standard 8710 and the NB-8710, the NB prefix is the critical difference, and it changes the installation substantially.

The NB Prefix: What "Less Bottom Rod" Actually Means

The standard Sargent 8710 uses two latch points-a top latch at the frame header and a bottom latch at the floor or threshold. The vertical rod connects the push bar down through the door to the bottom latch mechanism, and a separate floor or threshold strike receives that bottom latch when the door closes. Two-point latching gives you a more secure and rigid door closure, but it requires a clean floor or threshold installation to accept the bottom rod.

The NB-8710 eliminates the bottom rod entirely. You get one latch point-the top. The top rod activates the top latch only when the push bar is pressed. No bottom rod, no floor strike, no threshold cutout. This is the right specification when a bottom rod installation isn't feasible-when the floor surface is uneven, when a threshold or latch track threshold is already in place that conflicts with a floor strike, when retrofitting onto a door where the bottom rod chase wasn't installed, or simply when a single top latch point is sufficient for the security and code requirements of the opening.

Exit Only: What Function 10 Means at the Door

The 8710 function is exit only-ANSI function 10. There's no outside trim, no cylinder, no knob or lever on the exterior side. The push bar on the inside provides egress. From outside, the door can't be operated without separate outside trim added (which would change the function designation). This configuration is standard for stairwell doors, utility corridor exits, mechanical room access, and any door where one-directional egress is the requirement.

Model Code: Reading the F and What It Covers

The F suffix in NB-8710-F designates the 36-inch push rail. Sargent uses a letter-based rail sizing system for the 8700 series:

E covers doors 24 to 32 inches wide. F covers 33 to 36 inches. J covers 37 to 42 inches. G covers 43 to 48 inches.

No cutting is required when the door width matches the maximum of the range-a 36-inch door uses a 36-inch F rail with no field cuts. For narrower doors within the range, the rail can be cut down.

The NB-8710-F comes handed-specify RHR or LHR at time of order.

Auxiliary Controls with the NB-8710

Because this is the NB (less bottom rod) version, it's compatible with NB-306 and NB-313 auxiliary controls if your project needs cylinder dogging or other control features added later. Standard 8700 series auxiliary controls (306 and 313) are not the same-they're specific to the NB series. When ordering with an auxiliary control, specify function 10 for the exit device.

Specifications

Model: Sargent NB-8710-F

Series: Sargent 8700 Surface Vertical Rod

NB Designation: Less Bottom Rod, top latch only

Function: 8710-Exit Only (ANSI F10, no outside operation)

Rail Size: F-36" for 33" to 36" door widths

Grade: ANSI/BHMA A156.3 Grade 1

Listings: UL10C (Fire Exit Hardware), UL305 (Panic Hardware)

Top Strike: 646 surface applied, black nylon coated

Bottom Strike: Not required (no bottom rod)

Dogging: Hex key standard

Centerline Height: 41" from finished floor standard; 38" for elementary schools

Projection: Push bar neutral 3", depressed 2-1/8"

Rods: 1/2" brass, bronze, or stainless steel

Door Material: Wood or metal

Handing: RHR or LHR, specify at order

Finishes: 32D Satin Stainless Steel, 10, 4, 3, 10B, 32, BSP available

American Locksets has stocked Sargent 8700 series exit devices since 2001.