San Francisco 49ers Offense Offensive Formations Singleback Ace Pair Bunch Bunch TE Deuce Close Doubles Y Off Close Wing Flex Close Wing Pair Wing Tight Y Off Trio I Form Close Pro Slot Close Tight Twin TE Y Off Shotgun Bunch Wide Bunch Y-Flex Deuce Close Doubles HB Wk Doubles Y-Flex Empty Base Flex Split Close Split Close Pro Tight Tight Y Off Trey Trey Open Trey Y-Flex Wing Tight Y Trips Wk Strong I Close Y Off Weak I Z Close