Universal Distribution Stringing Block
Single-Conductor Capacity


  • High strength, low weight.
  • Urethane-lined, polished-groove, nylatron, or ductile-iron sheaves.
  • 2,500 lb. maximum working load.
  • Positive locking handle (a secure spring-loaded latch and large-ID pull-loop) on the side-gate assembly for easy conductor clip-in and for hot-stick operations.
  • High-efficiency, low-friction.
  • Forever Warranty™



About the XS-100B
The Sherman + Reilly XS-100B Universal Stringing Block is a light-weight, yet exceptionally rugged, reliable, and durable distribution stringing block. Combined with its family of associated hardware and accessories, it affords utilities and their contractors exceptional versatility in how and where it may be deployed and in the range of installation problems it can help solve. Its low-friction bearings render high block efficiency, which helps to maximize stringing distances while minimizing pulling tensions and reducing loads on stringing equipment.

The XS-100B’s light weight and durability derive from the materials and methods used to make it. The material used for the frame is “virgin” A356-T6 aluminum, which is an aluminum alloy with very tightly controlled proportions of other materials to assure optimum performance during manufacture and in the field. Virgin material is material that has not been mixed with scrap material, not even with scrap of what may have once been the same alloy. The fact that Sherman + Reilly uses “virgin” material assures that the material is exactly and only the pure and correct alloy, and that it has not been contaminated by impurities (notably iron) that often accompany non-virgin material.

XS-100B frames are cast (molded) as molten metal. The properties and purity of the A356-T6 Aluminum used by Sherman + Reilly assure that the molten metal flows smoothly and evenly throughout the mold, assuring proper and uniform density throughout the finished frame. Proper density and uniformity combined with the purity and metallic properties of the alloy assure that the frame is strong but light-weight, and assure that there are no internal voids or brittleness that could cause sudden complete failure of the block in the field.

The sheaves of the XS-100B are also made of the same virgin A356-T6 Aluminum as the frame. They are also similarly cast, but they have the additional manufacturing step of having the grooves and bearing surfaces machined for smoothness and precision fit. Combined with low-friction, lubricated-for-life bearings, the sheave materials, and how they are made assure high-efficiency and smooth-stringing performance.

How to order XS-100B Blocks
To order XS-100B blocks, will need to specify, sheave type (all blocks must be ordered with a sheave), cross-arm brackets, and fittings.

Sheave Types/Options
There are 4 options for sheave type. For more information about sheave options, refer to XS-100B Sheave Options found in the Publications section of this page.

Cross-Arm Brackets
Cross-arm brackets are the hardware attachments to the bottom of blocks that are used to affix blocks to cross-arms. Order your blocks with cross-arm brackets if the blocks will be used on cross-arms (either immediately or in the future). There are 3 choices of cross-arm bracket: Fastrap Universal Cross-arm Bracket, Speedlock Universal Cross-Arm Bracket, and the Standard Bracket.

Fittings are the hardware attachments that fit into the socket connector at the top of the blocks in order to hang the blocks from fixtures – hooks, lines, brackets, etc. Order your blocks with fittings if the blocks will hung or suspended (either immediately or in the future).

For More Information about the XS-100B Blocks contact your local Sherman + Reilly Representative or call Sherman + Reilly directly at 1-800-251-7780.

Maximum Working Load: 2,500 lb.
Efficiency: 98%
Maximum Conductor OD: 1 3/4 in.
Sheave OD: 7 in.
Sheave Groove Radius: 1 in.
Sheave Throat Width: 3 1/16 in.
Sheave Throat Height: Please refer to Product Sheet.
Sheave Rim Width: 3 in.
Width, overall, nom.: 7 in.
Height, overall, nom.: 14 11/16 in., without bracket
Height, overall, nom.: 15 13/16 in., with bracket, to base bottom
Frame Material: A356-T6 Aluminum (virgin)
Sheave Material, std.: A356-T6 Aluminum (virgin), excl. lining, if any
Sheave Material, opt.: Ductile iron or Nylatron
Sheave Lining Option: Urethane on aluminum
Materials, other: Please refer to Product Sheet.
Dimensions, other: Please refer to Product Sheet.
Weight, nom.: 9 1/4 lb. without base; 12 1/2 lb. with base
Hanging Hardware: Socket connector

GS-100 Grounding Stud
When a situation requires the block to be grounded, the model GS-100 grounding stud can be used. The stud provides a continuous and positive ground during stringing operations. The GS-100 grounding stud has been tested by an independent lab at multiple amps and cycles with satisfactory performance. The grounding stud is easily accessible for attaching or securing ground wire or clamp.

For more, please refer to the Product Sheet found on this page under Downloads.