Originally drafted in the third round in 2005 (94 overall), Adam Snyder rejoins the 49ers after a season with the division rival Arizona Cardinals, where he made 14 appearances last year.
Snyder originally signed a five-year contract with Arizona, but was released after just one season when the team drafted Jonathan Cooper in the most recent draft to make an immediate impact on the team's porous offensive line.
In his seven previous seasons in San Francisco, Snyder played all over the offensive line and could become a primary backup tackle on game days thanks to his versatility. He started at right guard in 13 games for the 49ers in 2011 before latching on in Arizona.
San Francisco doesn't have much depth at tackle behind starters Joe Staley and Anthony Davis. The team used a late-round draft pick Carter Bykowski, who will have to have a good training camp to earn a spot on the roster or practice squad.
Other reserve tackle candidates could include undrafted free agent Luke Marquardt and practice squad member Kenny Wiggins. Prior to this off-season, Alex Boone was the team's primary backup at tackle, but has established himself at right guard, earning Pro Bowl alternate status for his 2012 season.