Extractor fingers fit into flutes of broken tap and a few turns of a tap wrench removes broken tap. Size: 1/2" (12mm).
WALTON 10504 12MM / 1/2" 4-FLUTE TAP EXTRACTOR Made in USA
40050 Walton 1/2" 12mm Tap Extension Machine & Hand Style B
NEW Walton 10124 #12 5.5 mm 4 Flute Tap Extractor Replacement Finger (BN269)
Walton (12124) #12 5.5mm Extra Fingers for 4-Flute Tap Extractors - 8 QTY
NEW Walton 10122 #12 5.5 mm 2 Flute Tap Extractor Replacement Finger (BN269)
1 PIECE, WALTON - #12 (5.5mm) 2 FLUTE WALTON TAP EXTRACTOR C464-A