I-TSOP28-0.55-11.8 is a 28 pin TSOP package adapter for the pocket programmer.
Lead pitch is .55mm [.022"]
Body width 1.8mm [.465"]
Simply press down on the the top, insert the chip firmly into the chip opening, and then let go of the top. The socket pins clamp
down on the TSOP pins making contact and holding it in place. A bit of care must be used so as not to bend any pins.
*Legacy dimensions are in 
Index 33000 0.030