Imperial UNC UNF Tap and Die Set 3/16 1/4 5/16 3/8 7/16 1/2 Boxed Kit Taps SAE | eBay
936777-2 Fractional Tap/Hexagon Die Set, 14 Pcs. | Imperial Supplies
Groz 41-Piece Imperial Tap and Die Set | Tap Wrench | Die Holders | Thread Pitch Gauge | Hand Taps & Round Dies | Professional Grade| Carrying Case (10015): Amazon.com: Tools & Home Improvement
Marxman Hand Tap Set, Straight Flute, Series 110, Imperial, 3 Piece, 1187 Size, GroundUNC Thread Standa 82984 | Zoro