2014-15: Leinster are now in the pattern of releasing a European kit in alternate years to the normal 'home' and alternaitve shirts and this season's one is certainly an eye-catcher. While large swathes of navy and gold are not out of the ordinary, the split in the middle may make one question if they have been having a few too many in Kiely's or The Bridge before heading to the RDS.
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If the stripes were normal, it'd be easier for us to like it. Big Red Cloud won a Bank of Ireland competition to be sponsors for a day when the province played Castres in the Champions Cup in January.

The other two kits are the same as those worn in 2013-14. They feature the same cut and main features, though the striping configurations (12 on each, representing the counties of the province, rather than the four you think you see) are different.
2013-14: When the Leinster kit was launched in the summer of 2013, publicity shots showed the players in shorts which were the same shade of blue as the home. In early games, the navy set continued to be used before it was decided to revert back.

In the Heineken Cup, the new home socks were paired with the existing European shirt despite being noticeably darker. Gahan Meats won the competition to adorn the jerseys for the home game against Ospreys while the quarter-final loss to Toulon saw the white alternative socks used.

For both that game and the trip to Castres - the only time the white kit was worn in Europe - 'H Cup' sleeve patches had to feature.
2012-13: While the shirts remained the same as in the previous season, the shorts reverted to a simpler design, devoid of the intruding white stripes. One variation in the Pro12 saw Leinster wear the white socks for the trip to Italy to face Zebre.

The province also reverted to having a separate jersey for European outings. Like its 2010-11 predecessor, it was a lighter shade than the usual shirt and featured silver trim. The shirt was used in all six Heineken Cup pool games (sleeve patches the only variation), but Leinster failed to qualify for the knockout stages.

They did have the consolation of being parachuted into the Amlin Challenge Cup, however. In the quarter-finals of that competition, Leinster faced Wasps and wore white shorts and socks, but the shirts still carried the Heineken logos. For the semi-final and final against Biarritz and Stade Francais respectively, the proper sleeve patches were applied.