Table 1:

Structural comparison between different FDs

FD Type	Size	Braided Microfilaments^{^a}		Radiopaque Microfilaments	Flared End	Metal Coverage	Retrievable
FD Type	Size	No.	Material	Radiopaque Microfilaments	Flared End	Metal Coverage	Retrievable
Pipeline	3–5.5 mm	48	75% cobalt chromium and 25% platinum	NA	No	30%–35%	Yes^{^b}
Silk	2.5–5 mm	48	Nickel-titanium alloy	4 Platinum wires	Yes	35%–55%	Yes
Surpass	2.5–5 mm	2.5 mm (36)	Cobalt-chromium	12 Platinum wires	No	30%	NA
		3 and 4 mm (60)
		5 mm (84)
FRED	2.5–5.5 mm	Inner layer (48)	Nickel-titanium alloy	2 Tantalum wires	Yes	NA	Yes
FRED	2.5–5.5 mm	Outer layer (16)	Nickel-titanium alloy	2 Tantalum wires	Yes	NA	Yes
Tubridge	2.5–6.5 mm	<3.5 mm (46)	Nickel-titanium alloy	2 Platinum-iridium wires	Yes	30%–35%	Yes
Tubridge	2.5–6.5 mm	≥3.5 mm (62)	Nickel-titanium alloy	2 Platinum-iridium wires	Yes	30%–35%	Yes

Note:—NA indicates not applicable.
↵a Braided microfilaments in this table mean those main wires excluding microfilaments especially for radiopaque usage.
↵b Pipeline Flex embolization devices are retrievable.