Field Logic LLC — Patent Pending
One Cap. Three Functions. Zero Compromises.
TETHYRTM is the world's first 3-in-1 conduit cap — it seals out debris, anchors your pull string or pull tape, and puts a precision field layout mark right at your conduit stub-up. Available in two configurations: the TETHYR Thread Cap for threaded fittings and the TETHYR Slip Cap for PVC, RMC, or EMT conduit. 10 trade sizes, ¾" to 6".
🔒 Patent Pending · Designed for the Job Site · Built for the Trades
Two configurations, three functions each. Debris protection, pull string anchor, and field layout center mark — built into every TETHYRTM Thread Cap and Slip Cap.
Seals the end of your conduit from concrete, mud, and construction dust throughout the rough-in phase. The Thread Cap threads into the fitting; the Slip Cap plugs directly into the open end of the conduit — both create a tight, reliable seal.
An internal cavity molded into the cap gives you a dedicated anchor point to tie off pull string or pull tape — secure, consistent, and always there when you need it.
The overhanging top lip covers the rim of the fitting or conduit end, keeping debris out of threads and open conduit ends alike so everything is clean and ready when it's time to pull.
The recessed cross slot on top isn't just for tool engagement — it gives you a precise, identifiable center point for tape measure, string line, or survey layout right from your conduit stub-up.
Available from ¾" through 6" in both configurations. Thread Cap sizes match standard NPT fitting specs (14 TPI down to 8 TPI). Slip Cap sizes match standard PVC and GRC conduit ID — exact to spec, every size.
Two configurations for every job. The TETHYR Thread Cap threads into threaded fittings. The TETHYR Slip Cap inserts into the bare end of PVC, RMC, or EMT conduit. Same three functions, same sizes — choose the fit your job calls for.
Every size delivers all three functions: debris seal, pull-string anchor, and field layout cross. Thread Cap (FLT) is available now — Slip Cap (FLS) coming soon.
Installs on standard NPT threaded conduit fittings. ¾" through 6". Pricing live in the order builder below.
| Size | Cat # |
|---|---|
| ¾" | FLT75 |
| 1" | FLT100 |
| 1¼" | FLT125 |
| 1½" | FLT150 |
| 2" | FLT200 |
| 2½" | FLT250 |
| 3" | FLT300 |
| 3½" | FLT350 |
| 4" | FLT400 |
| 6" | FLT600 |
⚠ For temporary use during construction only. TETHYR™ is not designed or intended for use in a completed or energized electrical installation. Not listed, labeled, or rated under any electrical product standard (UL, NEC, or equivalent). Remove before final inspection.
TETHYRTM Thread Cap (FLT) — available now. Select quantities below. Free shipping on all orders. 25-unit minimum.
Need to share product details? Download the spec sheet (PDF)
Push-fit Slip Cap for PVC, RMC, and EMT conduit (FLS series) is in final production. For early availability or quote requests, contact us.
Field Logic LLC is an invention and technology company based in Washington State. We develop and commercialize tools and products designed to solve real problems in the trades.
TETHYRTM was conceived by someone who has seen firsthand how much time gets lost clearing debris from conduit and improvising pull-tape anchors on the job site. This product exists because no one else had built it right.
We're not a big box brand. We're a small team that moves fast and stands behind what we ship.
Made in USA · Field Logic LLC · Patent Pending