A strip (10) of collated fasteners (12), each having a shank (18) and a head (22) includes, a carrier (30) moulded from a polymeric material with a sleeve (32) for each fastener (12). Each sleeve (32) has an annular portion and a breakable portion (36), which breaks into two segments as the fastener (12) gripped by such a sleeve is driven. The breakable portion, which is notched at one end, has a pair of similar, laterally opposed, outwardly opening, continuously curved concave recesses with open windows, from which portions of the fastener shank (18) emerges. In a fastener-guiding tool, parallel ribs of a guiding device fit into such recesses, into close proximity with the emerging portions, so as to guide the strip between such ribs.