Dewalt DT70702 40 Piece Screwdriver Bit Set + Tough Case Fits TStak Caddy, Black - £13.95 @ Amazon

• 40 piece accessory set
• The accessories are impact rated for use with impact drivers TSTAK compatible
• Fits the DT70716 T-STAK caddy
• Model number: DT70702

Next best price is from CEF for £16.74

Modular, stackable small tough case. Designed for secure storage of accessories. Clear lid for easy identification. Easy bit removal and replacement. Bits securely lock into place. Use the locking system to connect the cases together, and securely stack on top of the medium Toughcase. Or, place into the accessory caddy for TSTAK compatible connection.

Additional Features

• TSTAK compatible to hold all your accessory sets in one place.
• Compatible with the TSTAK system via the Caddy and Large Tough Case.
• Easy bit removal and retention for user convenience.
• Bits lock into place to prevent them falling out when not in use.
• Optimized Tip Geometry for full fitment in the fastener and reduced cam-out.
• Full-fit head eliminates wobble and screw head rounding.
• Includes a drive guide with an extending sleeve for improved fastener stability and control.
• Includes nut drivers.