There are four variants of Tavors that have been available in Canada.

Gen 1 was imported by Canada Ammo, and came with a Mepro 21 optic clamped to the barrel. These units contained a military bolt and free floating firing pin, which were later replaced by IWI under concerns over slam fires when used with light primer ammunition. Some 15″ IDF CTAR barrels also came in during this time period. Looks like this:

The initial TAR21 imported by Canada Ammo

The Gen 1.5 was a $300 upgrade available for the last two Can-Am batches of Tavors. Gen 1.5 is identical in every way, except that it included a factory picatinny rail and its Mepro 21 used a quick detach mount. Many Canadians with Gen 1 Tavors have converted them to Gen 1.5 using 3rd party rails to allow for more optics than just the Meprolight. Looks like this:

TAR21 Tavor with aftermarket rail

North Sylva took over the IWI contract, and began importing Generation 2 Tavors that feature a full flattop rail. [I]Most[/I] of these have integral BUIS and often come with some unusual iron sights off the shelf. These units use a lighter polymer body and have a different texture than the Gen 1 and 1.5 models.

Imported by North Sylva, the Gen2 Tavor

IWI US Tavors have been imported to Canada by IrunGuns, although they are currently rare. These units come with 16″ or 18″ barrels. They are restricted, feature a lighter trigger, and have QD sling mounts in the hand guard and rear receiver. They are a flattop with integral BUIS, and have a body that is [I]very[/I] similar to the Gen 2. Looks like this:

SAR-21 Tavor with 16" Barrel in FDE

All Canadian Tavors are under the TAR-21 model name. The IWI US Tavors are called SAR-21s, on account of their unique trigger pack and receiver insert. The IWI US Tavors seem to be compatible in terms of barrels with Canadian Tavors, but BCG and trigger packs are certainly not. In depth compatibility between the TAR21 and SAR21 platforms has yet to be tested.